Aquarium Fish Antibiotics
Aquarium antibiotics dosed per gallon for fin rot, dropsy, columnaris and internal bacterial infection, including tablet and powder forms.
Related: All fish products
76 products
Bromhexine Powder Generic
Regular price $24.95 Save $-22.95A highly effective drying agent of mucus in upper and lower respiratory tracts caused by infection.
Combining with a respiratory antibiotic, such as Doxycycline, is highly recommended.
Bromhexine must be combined with any antibiotic used in the treatment of respiratory disease for the first four days of treatment.
Warning: May only be used in the treatment of sick pigeons and must be withdrawn 72 hours before basketing. Do not combine with Furazolidone or Furaltadone!
How to use
1 teaspoon (5 grams) per gallon of drinking water for 4 days. Change water daily.
Oxytetracycline Broad-Spectrum Fish Antibiotic Powder – 200 Gallons
Regular price $49.99 Save $-49.99Oxytetracycline Broad-Spectrum Fish Antibiotic Powder – 200 Gallons
Oxytetracycline Broad-Spectrum Fish Antibiotic Powder – 200 Gallons is a tetracycline-class antibacterial powder for ornamental fish with label-listed conditions involving susceptible gram-positive and gram-negative bacteria. This size provides label-directed coverage for up to 200 gallons when measured and applied according to the current product label.
Key Aquarium Treatment Features
- Supports label-directed care for raised scales, swollen belly, swim bladder inflammation and bloody fins or scales.
- Relevant to listed concerns associated with Aeromonas, Pseudomonas and myxobacterial organisms.
- Can be administered through aquarium water or incorporated into feed according to the current label.
Label-Listed Fish Health Concerns
This product may be considered when the visible signs and the current label are consistent with concerns such as:
- Raised scales
- Swollen belly
- Swim bladder inflammation
- Bloody fins
- Bloody scales
- Gill disease
- Marine ulcer disease
- Hemorrhagic septicemia
- Aeromonas
- Pseudomonas
- Myxobacterial infection
- Bacterial infection
Visible symptoms do not confirm a diagnosis. Similar signs may result from poor water quality, parasites, fungus, injury, toxins or environmental stress. Correct the aquarium environment and seek qualified aquatic guidance when the cause is uncertain.
Dosage and Application Directions
- Condition the aquarium water before measuring the powder.
- Use 1/4 teaspoon per 20 gallons every 24 hours.
- Complete a 25% water change before each repeat treatment.
- For label-directed feed use, mix 2 teaspoons or 1.2 grams per pound of food for 14–21 days.
- Calcium and magnesium can bind oxytetracycline. Consider water hardness and pH; when pH is 8.0 or higher or water is hard, the label suggests administration in food.
Label priority: Always compare these listing details with the instructions printed on the bottle you receive. The physical product label controls the amount, frequency, duration, compatibility and storage requirements.
Prepare the Treatment Aquarium
- Calculate dosage from the aquarium’s actual water volume, not its advertised capacity.
- Use a separate hospital or quarantine tank whenever practical.
- Test ammonia and nitrite before treatment and throughout the complete course.
- Remove activated carbon, UV or other equipment only when the current label directs you to do so.
- Maintain stable temperature and strong aeration while observing the fish closely.
Use a hospital aquarium whenever possible and monitor ammonia, nitrite, pH and hardness throughout the treatment period.
Coverage and Product Format
The concentrated powder format is designed for accurate measuring in a controlled treatment system. This package treats up to 200 gallons at the label-directed rate, making the coverage easy to compare with your hospital tank, quarantine aquarium or ornamental pond treatment volume.
wepetverse.com Product Information
wepetverse.com organizes aquarium treatments by active ingredient, intended use and total gallon coverage so fish keepers can compare products without relying only on brand nicknames. Review the current label, calculate actual water volume and select treatment according to the likely cause rather than symptoms alone.
Important Safety Notice
For ornamental aquarium and ornamental pond fish only. Not for human use or consumption. Do not use on fish intended for human consumption. Keep tightly closed and protected from children, animals, moisture, excessive heat and direct light. Use only as directed and consult a qualified aquatic veterinarian or fish-health professional when the condition is severe, recurring or unclear.
Oxytetracycline Broad-Spectrum Fish Antibiotic Powder – 1,000 Gallons
Regular price $89.99 Save $-89.99Oxytetracycline Broad-Spectrum Fish Antibiotic Powder – 1,000 Gallons
Oxytetracycline Broad-Spectrum Fish Antibiotic Powder – 1,000 Gallons is a tetracycline-class antibacterial powder for ornamental fish with label-listed conditions involving susceptible gram-positive and gram-negative bacteria. This size provides label-directed coverage for up to 1,000 gallons when measured and applied according to the current product label.
Key Aquarium Treatment Features
- Supports label-directed care for raised scales, swollen belly, swim bladder inflammation and bloody fins or scales.
- Relevant to listed concerns associated with Aeromonas, Pseudomonas and myxobacterial organisms.
- Can be administered through aquarium water or incorporated into feed according to the current label.
Label-Listed Fish Health Concerns
This product may be considered when the visible signs and the current label are consistent with concerns such as:
- Raised scales
- Swollen belly
- Swim bladder inflammation
- Bloody fins
- Bloody scales
- Gill disease
- Marine ulcer disease
- Hemorrhagic septicemia
- Aeromonas
- Pseudomonas
- Myxobacterial infection
- Bacterial infection
Visible symptoms do not confirm a diagnosis. Similar signs may result from poor water quality, parasites, fungus, injury, toxins or environmental stress. Correct the aquarium environment and seek qualified aquatic guidance when the cause is uncertain.
Dosage and Application Directions
- Condition the aquarium water before measuring the powder.
- Use 1/4 teaspoon per 20 gallons every 24 hours.
- Complete a 25% water change before each repeat treatment.
- For label-directed feed use, mix 2 teaspoons or 1.2 grams per pound of food for 14–21 days.
- Calcium and magnesium can bind oxytetracycline. Consider water hardness and pH; when pH is 8.0 or higher or water is hard, the label suggests administration in food.
Label priority: Always compare these listing details with the instructions printed on the bottle you receive. The physical product label controls the amount, frequency, duration, compatibility and storage requirements.
Prepare the Treatment Aquarium
- Calculate dosage from the aquarium’s actual water volume, not its advertised capacity.
- Use a separate hospital or quarantine tank whenever practical.
- Test ammonia and nitrite before treatment and throughout the complete course.
- Remove activated carbon, UV or other equipment only when the current label directs you to do so.
- Maintain stable temperature and strong aeration while observing the fish closely.
Use a hospital aquarium whenever possible and monitor ammonia, nitrite, pH and hardness throughout the treatment period.
Coverage and Product Format
The concentrated powder format is designed for accurate measuring in a controlled treatment system. This package treats up to 1,000 gallons at the label-directed rate, making the coverage easy to compare with your hospital tank, quarantine aquarium or ornamental pond treatment volume.
wepetverse.com Product Information
wepetverse.com organizes aquarium treatments by active ingredient, intended use and total gallon coverage so fish keepers can compare products without relying only on brand nicknames. Review the current label, calculate actual water volume and select treatment according to the likely cause rather than symptoms alone.
Important Safety Notice
For ornamental aquarium and ornamental pond fish only. Not for human use or consumption. Do not use on fish intended for human consumption. Keep tightly closed and protected from children, animals, moisture, excessive heat and direct light. Use only as directed and consult a qualified aquatic veterinarian or fish-health professional when the condition is severe, recurring or unclear.
Nitrofurazone Fish Antibiotic Powder for Ulcers & Fin Rot – 200 Gallons
Regular price $49.99 Save $-49.99Nitrofurazone Fish Antibiotic Powder for Ulcers & Fin Rot – 200 Gallons
Nitrofurazone Fish Antibiotic Powder for Ulcers & Fin Rot – 200 Gallons is a concentrated nitrofurazone antibacterial powder for ornamental fish with label-listed external bacterial signs involving skin, fins, sores and ulcers. This size provides label-directed coverage for up to 200 gallons when measured and applied according to the current product label.
Key Aquarium Treatment Features
- Supports label-directed care for red body areas, streaking, peeling tissue, open ulcers and wasting.
- Commonly considered for myxobacterial concerns, fin and tail rot, open sores and Vibrio-related signs.
- The current label also includes a separate dip-treatment method for controlled short-duration exposure.
Label-Listed Fish Health Concerns
This product may be considered when the visible signs and the current label are consistent with concerns such as:
- Open ulcers
- Open sores
- Fin rot
- Tail rot
- Red body streaks
- Red areas
- Peeling skin
- White body
- Wasting disease
- Myxobacterial infection
- Vibrio anguillarum
- Bacterial infection
- Dermal fungus
- Shipping injury complications
Visible symptoms do not confirm a diagnosis. Similar signs may result from poor water quality, parasites, fungus, injury, toxins or environmental stress. Correct the aquarium environment and seek qualified aquatic guidance when the cause is uncertain.
Dosage and Application Directions
- Condition the aquarium water and verify the actual treatment volume.
- Use 1/4 teaspoon per 30 gallons of aquarium water.
- A dose may be repeated after 24 hours after completing a 25–50% water change.
- The label describes a treatment period of 5–10 days.
- For dip treatment, follow the label exactly: 189–756 mg per 10 gallons for 1 hour, repeated daily for up to 10 days.
Label priority: Always compare these listing details with the instructions printed on the bottle you receive. The physical product label controls the amount, frequency, duration, compatibility and storage requirements.
Prepare the Treatment Aquarium
- Calculate dosage from the aquarium’s actual water volume, not its advertised capacity.
- Use a separate hospital or quarantine tank whenever practical.
- Test ammonia and nitrite before treatment and throughout the complete course.
- Remove activated carbon, UV or other equipment only when the current label directs you to do so.
- Maintain stable temperature and strong aeration while observing the fish closely.
Monitor ammonia and nitrite throughout use, treat in a hospital aquarium when possible and protect the powder from heat, moisture and bright light.
Coverage and Product Format
The concentrated powder format is designed for accurate measuring in a controlled treatment system. This package treats up to 200 gallons at the label-directed rate, making the coverage easy to compare with your hospital tank, quarantine aquarium or ornamental pond treatment volume.
wepetverse.com Product Information
wepetverse.com organizes aquarium treatments by active ingredient, intended use and total gallon coverage so fish keepers can compare products without relying only on brand nicknames. Review the current label, calculate actual water volume and select treatment according to the likely cause rather than symptoms alone.
Important Safety Notice
For ornamental aquarium and ornamental pond fish only. Not for human use or consumption. Do not use on fish intended for human consumption. Keep tightly closed and protected from children, animals, moisture, excessive heat and direct light. Use only as directed and consult a qualified aquatic veterinarian or fish-health professional when the condition is severe, recurring or unclear.
Nitrofurazone Fish Antibiotic Powder for Ulcers & Fin Rot – 1,000 Gallons
Regular price $89.99 Save $-89.99Nitrofurazone Fish Antibiotic Powder for Ulcers & Fin Rot – 1,000 Gallons
Nitrofurazone Fish Antibiotic Powder for Ulcers & Fin Rot – 1,000 Gallons is a concentrated nitrofurazone antibacterial powder for ornamental fish with label-listed external bacterial signs involving skin, fins, sores and ulcers. This size provides label-directed coverage for up to 1,000 gallons when measured and applied according to the current product label.
Key Aquarium Treatment Features
- Supports label-directed care for red body areas, streaking, peeling tissue, open ulcers and wasting.
- Commonly considered for myxobacterial concerns, fin and tail rot, open sores and Vibrio-related signs.
- The current label also includes a separate dip-treatment method for controlled short-duration exposure.
Label-Listed Fish Health Concerns
This product may be considered when the visible signs and the current label are consistent with concerns such as:
- Open ulcers
- Open sores
- Fin rot
- Tail rot
- Red body streaks
- Red areas
- Peeling skin
- White body
- Wasting disease
- Myxobacterial infection
- Vibrio anguillarum
- Bacterial infection
- Dermal fungus
- Shipping injury complications
Visible symptoms do not confirm a diagnosis. Similar signs may result from poor water quality, parasites, fungus, injury, toxins or environmental stress. Correct the aquarium environment and seek qualified aquatic guidance when the cause is uncertain.
Dosage and Application Directions
- Condition the aquarium water and verify the actual treatment volume.
- Use 1/4 teaspoon per 30 gallons of aquarium water.
- A dose may be repeated after 24 hours after completing a 25–50% water change.
- The label describes a treatment period of 5–10 days.
- For dip treatment, follow the label exactly: 189–756 mg per 10 gallons for 1 hour, repeated daily for up to 10 days.
Label priority: Always compare these listing details with the instructions printed on the bottle you receive. The physical product label controls the amount, frequency, duration, compatibility and storage requirements.
Prepare the Treatment Aquarium
- Calculate dosage from the aquarium’s actual water volume, not its advertised capacity.
- Use a separate hospital or quarantine tank whenever practical.
- Test ammonia and nitrite before treatment and throughout the complete course.
- Remove activated carbon, UV or other equipment only when the current label directs you to do so.
- Maintain stable temperature and strong aeration while observing the fish closely.
Monitor ammonia and nitrite throughout use, treat in a hospital aquarium when possible and protect the powder from heat, moisture and bright light.
Coverage and Product Format
The concentrated powder format is designed for accurate measuring in a controlled treatment system. This package treats up to 1,000 gallons at the label-directed rate, making the coverage easy to compare with your hospital tank, quarantine aquarium or ornamental pond treatment volume.
wepetverse.com Product Information
wepetverse.com organizes aquarium treatments by active ingredient, intended use and total gallon coverage so fish keepers can compare products without relying only on brand nicknames. Review the current label, calculate actual water volume and select treatment according to the likely cause rather than symptoms alone.
Important Safety Notice
For ornamental aquarium and ornamental pond fish only. Not for human use or consumption. Do not use on fish intended for human consumption. Keep tightly closed and protected from children, animals, moisture, excessive heat and direct light. Use only as directed and consult a qualified aquatic veterinarian or fish-health professional when the condition is severe, recurring or unclear.
Neomycin Sulfate Fish Antibiotic Powder for Fin Rot & Sores – 1,000 Gallons
Regular price $99.99 Save $-99.99Neomycin Sulfate Fish Antibiotic Powder for Fin Rot & Sores – 1,000 Gallons
Neomycin Sulfate Fish Antibiotic Powder for Fin Rot & Sores – 1,000 Gallons is a water-soluble neomycin sulfate antibacterial powder for ornamental fish showing label-listed signs associated with susceptible bacterial organisms. This size provides label-directed coverage for up to 1,000 gallons when measured and applied according to the current product label.
Key Aquarium Treatment Features
- Commonly selected for open sores, fin and body rot, internal swelling and loss of color.
- Relevant to label-listed concerns associated with Aeromonas, Pseudomonas and Myxobacteria.
- Can be applied in treatment water or prepared with feed according to the current product label.
Label-Listed Fish Health Concerns
This product may be considered when the visible signs and the current label are consistent with concerns such as:
- Open sores
- Fin rot
- Body rot
- Internal swelling
- Loss of color
- Body distortion
- Guppy disease
- Furunculosis
- Columnaris
- Popeye
- Gourami disease
- Bacterial infection
Visible symptoms do not confirm a diagnosis. Similar signs may result from poor water quality, parasites, fungus, injury, toxins or environmental stress. Correct the aquarium environment and seek qualified aquatic guidance when the cause is uncertain.
Dosage and Application Directions
- Prepare and condition the aquarium water before adding the powder.
- Use 1/4 teaspoon for each 10 gallons of actual treatment water.
- Repeat once every 24 hours for at least 3 days, completing an approximately one-third water change before each new dose.
- For label-directed medicated feed, use 1.5 grams per pound of fish food daily for 10 days.
- Do not combine with copper sulfate. Use a separate hospital or quarantine aquarium whenever practical.
Label priority: Always compare these listing details with the instructions printed on the bottle you receive. The physical product label controls the amount, frequency, duration, compatibility and storage requirements.
Prepare the Treatment Aquarium
- Calculate dosage from the aquarium’s actual water volume, not its advertised capacity.
- Use a separate hospital or quarantine tank whenever practical.
- Test ammonia and nitrite before treatment and throughout the complete course.
- Remove activated carbon, UV or other equipment only when the current label directs you to do so.
- Maintain stable temperature and strong aeration while observing the fish closely.
Monitor ammonia and nitrite closely because repeated antibacterial dosing may affect aquarium stability and biological filtration.
Coverage and Product Format
The concentrated powder format is designed for accurate measuring in a controlled treatment system. This package treats up to 1,000 gallons at the label-directed rate, making the coverage easy to compare with your hospital tank, quarantine aquarium or ornamental pond treatment volume.
wepetverse.com Product Information
wepetverse.com organizes aquarium treatments by active ingredient, intended use and total gallon coverage so fish keepers can compare products without relying only on brand nicknames. Review the current label, calculate actual water volume and select treatment according to the likely cause rather than symptoms alone.
Important Safety Notice
For ornamental aquarium and ornamental pond fish only. Not for human use or consumption. Do not use on fish intended for human consumption. Keep tightly closed and protected from children, animals, moisture, excessive heat and direct light. Use only as directed and consult a qualified aquatic veterinarian or fish-health professional when the condition is severe, recurring or unclear.
Neomycin Sulfate Fish Antibiotic Powder for Fin Rot & Sores – 200 Gallons
Regular price $59.99 Save $-59.99Neomycin Sulfate Fish Antibiotic Powder for Fin Rot & Sores – 200 Gallons
Neomycin Sulfate Fish Antibiotic Powder for Fin Rot & Sores – 200 Gallons is a water-soluble neomycin sulfate antibacterial powder for ornamental fish showing label-listed signs associated with susceptible bacterial organisms. This size provides label-directed coverage for up to 200 gallons when measured and applied according to the current product label.
Key Aquarium Treatment Features
- Commonly selected for open sores, fin and body rot, internal swelling and loss of color.
- Relevant to label-listed concerns associated with Aeromonas, Pseudomonas and Myxobacteria.
- Can be applied in treatment water or prepared with feed according to the current product label.
Label-Listed Fish Health Concerns
This product may be considered when the visible signs and the current label are consistent with concerns such as:
- Open sores
- Fin rot
- Body rot
- Internal swelling
- Loss of color
- Body distortion
- Guppy disease
- Furunculosis
- Columnaris
- Popeye
- Gourami disease
- Bacterial infection
Visible symptoms do not confirm a diagnosis. Similar signs may result from poor water quality, parasites, fungus, injury, toxins or environmental stress. Correct the aquarium environment and seek qualified aquatic guidance when the cause is uncertain.
Dosage and Application Directions
- Prepare and condition the aquarium water before adding the powder.
- Use 1/4 teaspoon for each 10 gallons of actual treatment water.
- Repeat once every 24 hours for at least 3 days, completing an approximately one-third water change before each new dose.
- For label-directed medicated feed, use 1.5 grams per pound of fish food daily for 10 days.
- Do not combine with copper sulfate. Use a separate hospital or quarantine aquarium whenever practical.
Label priority: Always compare these listing details with the instructions printed on the bottle you receive. The physical product label controls the amount, frequency, duration, compatibility and storage requirements.
Prepare the Treatment Aquarium
- Calculate dosage from the aquarium’s actual water volume, not its advertised capacity.
- Use a separate hospital or quarantine tank whenever practical.
- Test ammonia and nitrite before treatment and throughout the complete course.
- Remove activated carbon, UV or other equipment only when the current label directs you to do so.
- Maintain stable temperature and strong aeration while observing the fish closely.
Monitor ammonia and nitrite closely because repeated antibacterial dosing may affect aquarium stability and biological filtration.
Coverage and Product Format
The concentrated powder format is designed for accurate measuring in a controlled treatment system. This package treats up to 200 gallons at the label-directed rate, making the coverage easy to compare with your hospital tank, quarantine aquarium or ornamental pond treatment volume.
wepetverse.com Product Information
wepetverse.com organizes aquarium treatments by active ingredient, intended use and total gallon coverage so fish keepers can compare products without relying only on brand nicknames. Review the current label, calculate actual water volume and select treatment according to the likely cause rather than symptoms alone.
Important Safety Notice
For ornamental aquarium and ornamental pond fish only. Not for human use or consumption. Do not use on fish intended for human consumption. Keep tightly closed and protected from children, animals, moisture, excessive heat and direct light. Use only as directed and consult a qualified aquatic veterinarian or fish-health professional when the condition is severe, recurring or unclear.
Kanamycin Sulfate Broad-Spectrum Fish Antibiotic Powder – 200 Gallons
Regular price $49.99 Save $-49.99Kanamycin Sulfate Broad-Spectrum Fish Antibiotic Powder – 200 Gallons
Kanamycin Sulfate Broad-Spectrum Fish Antibiotic Powder – 200 Gallons is a broad-spectrum kanamycin sulfate powder for ornamental aquarium fish, including many scaleless species when the current label directions are followed. This size provides label-directed coverage for up to 200 gallons when measured and applied according to the current product label.
Key Aquarium Treatment Features
- Provides label-listed activity against gram-positive and gram-negative bacterial concerns.
- Commonly considered for fin and tail rot, mouth damage, cloudy eyes, popeye and related infections.
- May be administered through aquarium water, with label guidance also available for medicated pellets.
Label-Listed Fish Health Concerns
This product may be considered when the visible signs and the current label are consistent with concerns such as:
- Fin rot
- Tail rot
- Mouth fungus
- Mouth sores
- Eye sores
- Cloudy eyes
- Protruding eyes
- Popeye
- Molly disease
- Tetra disease
- Cyanobacteria
- Red slime
- Hemorrhagic septicemia
- Aeromonas
- Pseudomonas
- Myxobacteria
- Bacterial infection
Visible symptoms do not confirm a diagnosis. Similar signs may result from poor water quality, parasites, fungus, injury, toxins or environmental stress. Correct the aquarium environment and seek qualified aquatic guidance when the cause is uncertain.
Dosage and Application Directions
- Condition the aquarium water and calculate the true treatment volume before dosing.
- Use 1/4 teaspoon for each 20 gallons of water.
- Repeat every 24 hours after completing a 25% water change.
- Continue for 5–7 days. The label recommends half the standard amount for especially sensitive fish such as tetras and neons.
- Monitor ammonia and nitrite throughout the course because kanamycin may interfere with biological filtration.
Label priority: Always compare these listing details with the instructions printed on the bottle you receive. The physical product label controls the amount, frequency, duration, compatibility and storage requirements.
Prepare the Treatment Aquarium
- Calculate dosage from the aquarium’s actual water volume, not its advertised capacity.
- Use a separate hospital or quarantine tank whenever practical.
- Test ammonia and nitrite before treatment and throughout the complete course.
- Remove activated carbon, UV or other equipment only when the current label directs you to do so.
- Maintain stable temperature and strong aeration while observing the fish closely.
A dedicated hospital aquarium is strongly preferred so filtration, water quality and fish response can be observed without exposing the full display system.
Coverage and Product Format
The concentrated powder format is designed for accurate measuring in a controlled treatment system. This package treats up to 200 gallons at the label-directed rate, making the coverage easy to compare with your hospital tank, quarantine aquarium or ornamental pond treatment volume.
wepetverse.com Product Information
wepetverse.com organizes aquarium treatments by active ingredient, intended use and total gallon coverage so fish keepers can compare products without relying only on brand nicknames. Review the current label, calculate actual water volume and select treatment according to the likely cause rather than symptoms alone.
Important Safety Notice
For ornamental aquarium and ornamental pond fish only. Not for human use or consumption. Do not use on fish intended for human consumption. Keep tightly closed and protected from children, animals, moisture, excessive heat and direct light. Use only as directed and consult a qualified aquatic veterinarian or fish-health professional when the condition is severe, recurring or unclear.
Kanamycin Sulfate Broad-Spectrum Fish Antibiotic Powder – 1,000 Gallons
Regular price $89.99 Save $-89.99Kanamycin Sulfate Broad-Spectrum Fish Antibiotic Powder – 1,000 Gallons
Kanamycin Sulfate Broad-Spectrum Fish Antibiotic Powder – 1,000 Gallons is a broad-spectrum kanamycin sulfate powder for ornamental aquarium fish, including many scaleless species when the current label directions are followed. This size provides label-directed coverage for up to 1,000 gallons when measured and applied according to the current product label.
Key Aquarium Treatment Features
- Provides label-listed activity against gram-positive and gram-negative bacterial concerns.
- Commonly considered for fin and tail rot, mouth damage, cloudy eyes, popeye and related infections.
- May be administered through aquarium water, with label guidance also available for medicated pellets.
Label-Listed Fish Health Concerns
This product may be considered when the visible signs and the current label are consistent with concerns such as:
- Fin rot
- Tail rot
- Mouth fungus
- Mouth sores
- Eye sores
- Cloudy eyes
- Protruding eyes
- Popeye
- Molly disease
- Tetra disease
- Cyanobacteria
- Red slime
- Hemorrhagic septicemia
- Aeromonas
- Pseudomonas
- Myxobacteria
- Bacterial infection
Visible symptoms do not confirm a diagnosis. Similar signs may result from poor water quality, parasites, fungus, injury, toxins or environmental stress. Correct the aquarium environment and seek qualified aquatic guidance when the cause is uncertain.
Dosage and Application Directions
- Condition the aquarium water and calculate the true treatment volume before dosing.
- Use 1/4 teaspoon for each 20 gallons of water.
- Repeat every 24 hours after completing a 25% water change.
- Continue for 5–7 days. The label recommends half the standard amount for especially sensitive fish such as tetras and neons.
- Monitor ammonia and nitrite throughout the course because kanamycin may interfere with biological filtration.
Label priority: Always compare these listing details with the instructions printed on the bottle you receive. The physical product label controls the amount, frequency, duration, compatibility and storage requirements.
Prepare the Treatment Aquarium
- Calculate dosage from the aquarium’s actual water volume, not its advertised capacity.
- Use a separate hospital or quarantine tank whenever practical.
- Test ammonia and nitrite before treatment and throughout the complete course.
- Remove activated carbon, UV or other equipment only when the current label directs you to do so.
- Maintain stable temperature and strong aeration while observing the fish closely.
A dedicated hospital aquarium is strongly preferred so filtration, water quality and fish response can be observed without exposing the full display system.
Coverage and Product Format
The concentrated powder format is designed for accurate measuring in a controlled treatment system. This package treats up to 1,000 gallons at the label-directed rate, making the coverage easy to compare with your hospital tank, quarantine aquarium or ornamental pond treatment volume.
wepetverse.com Product Information
wepetverse.com organizes aquarium treatments by active ingredient, intended use and total gallon coverage so fish keepers can compare products without relying only on brand nicknames. Review the current label, calculate actual water volume and select treatment according to the likely cause rather than symptoms alone.
Important Safety Notice
For ornamental aquarium and ornamental pond fish only. Not for human use or consumption. Do not use on fish intended for human consumption. Keep tightly closed and protected from children, animals, moisture, excessive heat and direct light. Use only as directed and consult a qualified aquatic veterinarian or fish-health professional when the condition is severe, recurring or unclear.
Fish Zole Metronidazole 250mg & 500mg | Fish Antibiotic
Regular price $40.99 Save $-40.99Fish Zole Metronidazole 250mg & 500mg | Fish Antibiotic
Fish Zole (Fix Zole) is a metronidazole antibacterial treatment in tablet form for ornamental aquarium fish and non-food pet birds.
Each tablet supplies 250 mg or 500 mg of metronidazole and is made in the United States by Aqua Soma Labs. Hobbyists commonly use it to help manage suspected protozoan problems in a hospital or quarantine tank, where dosing and observation are easier to control.
Aquarists have known this metronidazole tablet under earlier names, including the discontinued Thomas Labs Fish Zole and Fish Zole Forte, Aqua-Zole, fishzole, and fishbiotic metronidazole.
Fix Zole is the current Aqua Soma Labs version, replacing those older products with the same metronidazole strengths of 250 mg or 500 mg per tablet. Keepers who previously used MetroPlex may find this a convenient tablet-based option.
Hobbyists use Fix Zole to help manage internal parasites and intestinal protozoan flagellates such as Hexamita and Spironucleus.
These problems can appear through feeding changes, unusual droppings, weight loss, behavioral changes, or visible physical signs in certain freshwater fish.
Metronidazole works against certain protozoa and anaerobic organisms. When used as directed, it can form part of a broader care plan that includes stable water quality, reduced stress, and appropriate nutrition.
It is not intended for ich or flukes, and it is not normally the first choice for typical fin rot unless the underlying cause has been confirmed by an aquatic professional.
Fix Zole from Aqua Soma Labs delivers 250 mg or 500 mg of metronidazole per tablet in 60-count bottles with fresh expiration dates.
Choose the tablet strength that matches your treatment-tank volume and treatment plan. Tablets may be pre-dissolved in a small cup of aquarium water before being added evenly to the treatment tank.
Use Fix Zole when fish or pet birds show signs that may be associated with protozoan flagellates or anaerobic-sensitive problems.
Fish-Specific Symptoms
- Loss of appetite or gradual weight loss
- White, stringy droppings
- Hole-in-the-head lesions or pits along the head and lateral line
- Malawi bloat or cichlid bloat
- Swollen abdomen
- Faded color, darkening, or body discoloration
- Lethargy, hiding, or reduced activity
- Sudden decline in cichlids or discus associated with Hexamita or Spironucleus
Bird-Specific Symptoms Under Avian Veterinary Guidance
- Yellow plaques in the throat or crop
- Canker or trichomonosis
- Pigeon canker, especially in racing pigeons
- Frounce in falcons, hawks, owls, and other raptors
- Loose or watery droppings possibly associated with giardia
- Reduced appetite or weight loss
- Difficulty swallowing or visible discomfort while eating
- Fluffed-up feathers or lethargy
Supporting treatment with clean water, stable temperature, low stress, and appropriate husbandry helps reduce setbacks and improve outcomes.
For pet birds, always confirm the diagnosis with an avian veterinarian before administering metronidazole.
Order online: Fix Zole ships from our United States warehouse the same business day according to the current order-processing schedule.
Fish Zole vs Fix Zole: What Changed?
If you previously used Thomas Labs Fish Zole, Fish Zole Forte, or Aqua-Zole by Aqua Soma Labs, here is what you need to know about Fix Zole.
Same as Fish Zole, Fish Zole Forte, and Aqua-Zole
Fix Zole uses the same metronidazole that hobbyists relied on under the Thomas Labs Fish Zole, Fish Zole Forte, and Aqua Soma Labs Aqua-Zole names.
New Fix Product Line
Fix Zole is produced by Aqua Soma Labs, which now manufactures the Fix line after Thomas Labs discontinued its Fish Zole products.
Same 60-Count Bottles
Each bottle contains 60 tablets. Choose between the 250 mg and 500 mg strengths according to the treatment-tank size and plan.
Updated Packaging, Same Formula
The brand name, bottle design, and label have changed, while the metronidazole tablet strengths remain familiar.
Benefits of Fix Zole for Fish & Birds
Targeted Protozoan Support
Commonly used to help manage internal parasites and protozoan flagellates such as Hexamita and Spironucleus, which may be associated with appetite loss, weight loss, white stringy droppings, Malawi bloat, and hole-in-the-head symptoms.
Stocked and Ready to Ship
Fix Zole ships from a United States warehouse according to the current processing schedule, helping aquarium keepers obtain treatment quickly when concerning signs appear.
Avian Vet-Guided Option
In non-food pet birds, metronidazole may be used under avian veterinary guidance for specific protozoal concerns such as giardia, frounce, and pigeon canker caused by trichomonosis.
Flexible 250 mg or 500 mg Tablets
Choose the strength that fits your treatment setup. A consistent amount per tablet helps aquarium keepers scale treatment across different tank volumes.
Ideal for Hospital Tanks and Quarantine
A separate hospital tank makes observation and dosing easier while helping protect the display aquarium's biological filter and sensitive tank mates.
Fits a Complete Care Plan
Treatment works best when combined with stable temperature, clean water, appropriate feeding, good aeration, and reduced environmental stress.
Targeted, Not a One-Size-Fits-All Remedy
Fix Zole is not normally used for ich, gill flukes, Costia, fungus, or ordinary fin rot unless the cause has been professionally identified.
Usage Guidelines & Instructions
Set Up a Separate Treatment Area
Move affected fish to a dedicated hospital or quarantine tank whenever possible.
This allows you to monitor behavior, control dosing more precisely, and reduce unnecessary exposure in the main display aquarium.
Directions for Fish Aquariums
Pre-dissolve the tablet in a small cup of aquarium water, then distribute the prepared solution evenly across the treatment tank.
250 mg strength: Add one 250 mg tablet per 10 gallons or 38 litres of treatment water.
500 mg strength: Add one 500 mg tablet per 20 gallons or 76 litres of treatment water.
Repeat the dose every 24 hours and perform a partial water change between treatments.
Adjust the Filtration
Remove activated carbon and other chemical filtration media during treatment.
Keep strong aeration running because activated carbon can reduce the amount of metronidazole available in the treatment water.
Continue Treatment and Monitor Results
Continue daily treatment for 5 to 10 days and do not exceed 10 days unless specifically directed by a qualified aquatic veterinarian.
If there is no improvement within five days, discontinue treatment and consult an aquatic professional.
Use in Pet Birds Under Veterinary Guidance
Administer metronidazole to non-food pet birds only under the direction of an avian veterinarian.
The veterinarian should confirm the diagnosis and determine the amount, frequency, and duration based on the bird's species, weight, and condition.
Tablets may be given whole, divided, or crushed into soft food only as specifically instructed.
Fix Zole Amounts by Aquarium Size
| Tank volume | Metronidazole per use | 250 mg tablets | 500 mg tablets |
|---|---|---|---|
| 10 gallons (38 L) | 250 mg | 1 tablet | Not applicable |
| 20 gallons (76 L) | 500 mg | 2 tablets | 1 tablet |
| 30 gallons (114 L) | 750 mg | 3 tablets | 1 tablet plus one 250 mg tablet |
| 40 gallons (151 L) | 1,000 mg | 4 tablets | 2 tablets |
| 55 gallons (208 L) | Approximately 1,375 mg | 5 to 6 tablets | Approximately 3 tablets |
What to Expect During Treatment
Days 1 to 2
Fish may hide or eat less while treatment begins. Maintain the schedule and keep aeration strong.
Days 3 to 5
Look for improving appetite, more normal droppings, and steadier activity. Stop and seek professional advice if the fish worsen or no change is seen by day five.
Days 5 to 10
Complete the recommended treatment period even when improvement appears. After treatment, perform a partial water change and restore activated carbon.
What You Need Before You Start
Prepare the following supplies before administering the first treatment:
- A separate hospital or quarantine tank
- A suitable heater
- An air stone or established sponge filter
- An ammonia and nitrite test kit
- Aquarium dechlorinator
- A small net for gentle transfer
- A clean cup for pre-dissolving each tablet
Pro Tip: After treatment, perform a partial water change and reintroduce activated carbon, if normally used, to help clear remaining treatment from the aquarium water.
How Fix Zole Works
Fix Zole uses metronidazole, an ingredient aquarium keepers have relied on for years for certain protozoan and anaerobic-sensitive problems.
In practical terms, metronidazole works against specific protozoa and anaerobic organisms, giving affected fish a better opportunity to recover when the underlying condition is susceptible to it.
This is why aquarium keepers use it when they suspect intestinal flagellates such as Hexamita and Spironucleus rather than for ich, flukes, fungal problems, or typical fin rot.
Each tablet also contains standard inactive ingredients that help hold the tablet together, support storage stability, and allow the tablet to disperse when mixed with water.
The exact inactive ingredient list may vary by batch and may not always be publicly listed.
Safety and Tank Notes
When used as directed, Fix Zole usually causes no problems in ornamental aquarium fish and non-food pet birds.
Incorrect amounts, extended treatment, unnecessary repeat treatments, or combining multiple products can increase stress and the risk of unwanted effects.
Fish
Possible reactions include temporarily reduced appetite, mild lethargy, or hiding behavior.
If severe distress develops, including rapid gill movement, loss of balance, surface gasping, or lying on the bottom, stop treatment, increase aeration, perform a partial water change, and seek aquatic veterinary advice.
Birds
Use metronidazole only under avian veterinary guidance.
Possible reactions may include reduced appetite, loose or changed droppings, and lethargy, particularly if the bird is sensitive or the administered amount is incorrect.
If the bird becomes fluffed up, inactive, or stops eating, discontinue use and contact an avian veterinarian.
Invertebrates
Sensitivity can vary between shrimp, snails, corals, and other invertebrates.
Whenever possible, treat fish in a separate hospital tank rather than dosing a display aquarium containing sensitive invertebrates.
Safe Use in Your System
Do not combine Fix Zole with other treatments unless advised by a qualified professional.
Avoid routine preventative use. If symptoms persist or return, confirm the diagnosis before repeating treatment.
Storage & Handling
Store Fix Zole at a controlled room temperature of 59–86°F or 15–30°C in a cool, dry place.
Keep the container tightly closed to protect the tablets from moisture and light.
Keep out of reach of children and pets.
Important Safety Warning: Fix Zole is intended for ornamental aquarium fish and non-food pet birds only. It is not for animals raised for food. Always follow current label directions.
Shipping & Returns
Shipping Policy
Orders ship from our United States warehouse within one business day through USPS or UPS.
Shipping rates and estimated delivery times are calculated at checkout.
Review Shipping Policy →Refund Policy
If there is an issue with your order, eligible items may be returned or exchanged within 30 days according to the current store guidelines.
Review the refund policy before sending any product back.
Review Refund Policy →Frequently Asked Questions
What is Fix Zole used for in aquarium fish and pet birds?
Fix Zole contains metronidazole and is used for certain protozoan and anaerobic-sensitive problems in ornamental fish. These may include Hexamita, Spironucleus, white stringy droppings, internal flagellates, Malawi bloat, and hole-in-the-head symptoms.
Use in non-food pet birds should occur only under avian veterinary guidance.
What is in Fix Zole?
Each tablet contains either 250 mg or 500 mg of metronidazole. Both strengths are supplied in 60-count bottles.
What does metronidazole treat in fish?
Metronidazole is generally used against certain internal protozoa, intestinal flagellates, and anaerobic organisms. It is commonly associated with treatment plans for Hexamita and Spironucleus in susceptible ornamental fish.
Is Fix Zole the same as Fish Zole or Fish Zole Forte?
Fix Zole is presented as the current Aqua Soma Labs replacement for the discontinued Fish Zole and Fish Zole Forte products. The familiar 250 mg and 500 mg metronidazole tablet strengths remain available.
Is Fix Zole the same as Aqua-Zole by Aqua Soma Labs?
Fix Zole is the updated Fix-brand version of the metronidazole tablets previously sold under names such as Aqua-Zole.
Will Fix Zole harm my tank's biological filter?
Treatment may disturb aquarium balance, particularly when used in a display aquarium. A separate hospital tank is preferred, and ammonia and nitrite should be monitored throughout treatment.
How do I choose between 250 mg and 500 mg tablets?
Choose the strength according to the treatment-tank volume. The supplied guide uses one 250 mg tablet per 10 gallons or one 500 mg tablet per 20 gallons.
Can I give Fix Zole to my dog or cat?
No. This product is labeled for ornamental aquarium fish and non-food pet birds. It is not intended for dogs, cats, humans, or food-producing animals.
Does metronidazole help with hole-in-the-head symptoms?
Aquarium keepers commonly use metronidazole when hole-in-the-head symptoms are suspected to involve intestinal flagellates such as Hexamita or Spironucleus. Similar lesions may have other causes, so diagnosis is important.
Will Fix Zole treat ich or gill flukes?
Fix Zole is not normally used for ich, white spot disease, or gill flukes. Those conditions generally require different treatment approaches.
Can Fix Zole treat fin rot or other bacterial infections?
Fix Zole is not normally the first choice for typical fin rot. It is more commonly used for certain protozoan flagellates and anaerobic-sensitive problems.
Can I use Fix Zole as routine prevention?
Routine preventative use is not recommended. Treatment should be based on observed symptoms, the product label, and professional guidance when the diagnosis is uncertain.
How long should I treat with Fix Zole?
The supplied directions describe treatment every 24 hours for 5 to 10 days, without exceeding 10 days. Follow the current bottle label and discontinue if no improvement is seen within five days.
How much metronidazole do I use per gallon?
The supplied reference is 250 mg per 10 gallons, approximately 25 mg per gallon. Pre-dissolve the tablet in aquarium water and dose according to the actual water volume of the treatment tank.
Is Fix Zole safe in saltwater tanks?
Fix Zole is presented for freshwater and saltwater treatment tanks. A separate hospital tank is recommended, especially when the display aquarium contains corals or other invertebrates.
Is Fix Zole reef-safe or safe with shrimp and snails?
Sensitivity varies by species. Treat fish separately whenever possible rather than exposing shrimp, snails, corals, and other invertebrates.
Can I combine Fix Zole with other treatments?
Do not combine treatments unless a veterinarian or qualified aquatic professional specifically recommends the combination.
How do I administer metronidazole to pet birds?
Administer metronidazole to non-food pet birds only under avian veterinary direction. The veterinarian must determine the amount, administration method, frequency, and duration.
How soon should I see improvement with Fix Zole?
Some improvement may become visible within three to five days through increased appetite, more normal droppings, and improved activity. Stop and seek professional advice if the animal worsens or no improvement is seen within five days.
Where can I buy metronidazole for fish online?
Fix Zole 250 mg and 500 mg tablets can be ordered through this online store and shipped according to the current United States warehouse processing and shipping policy.
More Fish & Bird Treatments
Fix Mox (Amoxicillin) 250/500 mg
A treatment for fin rot, dropsy, ulcers, and other bacterial infections in ornamental fish. Available in 30-count and 100-count capsules.
Shop Fix Mox →Fix Doxy (Doxycycline) 100 mg
A treatment for columnaris, respiratory infections, and Mycoplasma concerns in ornamental fish and non-food pet birds. Available in 30-count and 60-count tablets.
Shop Fix Doxy →Fix Zithro (Azithromycin) 250 mg
A treatment for fin rot, columnaris, gill disease, and avian respiratory concerns. Available in 12-count and 30-count tablets.
Shop Fix Zithro →Fix Cin (Clindamycin) 150 mg
A treatment for Gram-positive bacterial problems, including skin and soft-tissue concerns, in ornamental fish.
Shop Fix Cin →Fix Sulfa (SMZ/TMP) 960 mg
A treatment used against a range of bacterial problems in ornamental aquarium fish.
Shop Fix Sulfa →Fix Pen (Penicillin) 500 mg
A treatment for Gram-positive bacterial problems in ornamental fish and non-food pet birds.
Shop Fix Pen →Fix Flex (Cephalexin) 250/500 mg
A treatment for fin rot, ulcers, and bacterial skin problems in ornamental fish and non-food pet birds.
Shop Fix Flex →Fix Flox (Ciprofloxacin) 500 mg
A treatment for Gram-negative bacterial problems including fin rot, ulcers, columnaris, and septicemia.
Shop Fix Flox →Browse All Treatments
Explore our complete Fish & Bird Treatments Collection for more Fix line products and related care.
Explore the Collection →Guides and Treatment Tips
Visit the Fish & Bird Care Blog for practical usage guides, aquarium water-care advice, and treatment tips.
Visit the Blog →Transparency & Verification
How Product Information Is Verified
Who is responsible for this page: The store editorial team responsible for reviewing and maintaining product information.
Verification snapshot: This page is written from the current product label for this item and reviewed for accuracy and consistency before publishing.
How We Verify Product Information
Label-First Accuracy
Directions, treatment duration, storage, and warnings are taken from the current product label for this item.
Specification Validation
Key information such as ingredient names, tablet strengths, and bottle counts is cross-checked against available manufacturer specifications.
Consistency Checks
Product pages are reviewed for consistent directions, strengths, storage details, and warnings across all sections.
Updates
Pages are updated when product labels, packaging, tablet strengths, or manufacturer information changes.
See something that does not match the product you received? Please contact us so the page can be reviewed and updated.
Fish Flex Cephalexin 250mg & 500mg | Fish Antibiotic
Regular price $18.95 Save $-18.95Fish Cephalexin Capsules - Fish & Bird Antibacterial Treatment 250 mg / 500 mg
Fish Flex (Fix Flex) is an antibacterial treatment in capsule form for ornamental aquarium fish and non-food pet birds.
Made by Aqua Soma Labs, it supplies cephalexin in 250 mg and 500 mg capsule strengths and is available in bottles containing 30 or 100 capsules with clearly printed expiration dates.
Often called Fish Flex, Fin Flex, or simply fishflex in the aquarium community, this product is an online alternative to discontinued Thomas Labs Fish Flex, Fish Flex Forte, Fish Aid Cephalexin, Aqua Ceph 500 mg, Aqua Flex, and FISHBIOTIC Cephalexin products.
Aquarium keepers may also search for it as fish cephalexin, fish cephalexin 500 mg, or cephalexin for fish.
It is used to help manage common bacterial concerns such as fin and tail rot, skin ulcers, infected wounds and lesions, red patches, pop-eye, and dropsy or pinecone disease in freshwater and saltwater aquariums.
Under veterinary guidance, bird keepers may also use cephalexin as part of a treatment plan for bumblefoot, skin infections, or joint infections in pigeons and other non-food pet birds.
The capsules can be opened so the powder disperses quickly through aquarium water in a separate hospital or quarantine tank.
The availability of two strengths and two bottle sizes gives aquarium and bird keepers flexible options, whether maintaining one hospital tank, several community aquariums, or a veterinarian-directed aviary treatment plan.
Consider treatment when early signs of bacterial stress appear, including ragged fins, red or pale fin edges, open sores, localized swelling, cloudy body patches, pop-eye, or persistent appetite loss.
Fish-Specific Symptoms
- Fin and tail rot with frayed or ragged fins
- Skin ulcers, open sores, and infected wounds
- Red or cloudy patches on the body
- Pop-eye or exophthalmia
- Dropsy or pinecone disease
- Localized swelling
- Appetite loss or listless behavior
Bird-Specific Symptoms Under Veterinary Guidance
- Bumblefoot or swollen foot pads
- Skin irritation, redness, or infection
- Joint infection or swelling
- Ruffled or fluffed feathers
- Reduced activity
- Persistent appetite loss
Addressing possible bacterial problems early, together with suitable water quality, good housing, reduced stress, and advice from an aquatic or avian professional, helps maintain a stable aquarium or aviary.
Fix Flex is formulated, labeled, and sold exclusively as an antibacterial treatment for ornamental aquariums and non-food pet birds.
Order online for same-day dispatch on qualifying orders placed before 1:30 p.m. CT, Monday through Friday. Orders ship from our United States warehouse through USPS or UPS.
Fish Flex vs Fix Flex: What Changed?
If you previously purchased Thomas Labs Fish Flex, Fish Flex Forte, Aqua Ceph, Aqua Flex, or FISHBIOTIC Cephalexin, here is what has changed and what remains the same.
Same Cephalexin
Fix Flex contains cephalexin in the same familiar 250 mg and 500 mg capsule strengths associated with older Fish Flex and Aqua Ceph products.
New Manufacturer
Fix Flex is made in the United States by Aqua Soma Labs, replacing the discontinued Thomas Labs line.
Same Capsule Form
The capsules can be opened so the powder can be mixed into aquarium water or administered to birds exactly as directed by an avian veterinarian.
Two Strengths and Two Bottle Sizes
Choose 250 mg or 500 mg capsules in 30-count or 100-count bottles according to the aquarium volume and treatment plan.
Benefits of Fix Flex for Fish & Birds
Bacterial Support for Fish and Birds
Fix Flex provides cephalexin for ornamental aquarium fish and non-food pet birds and may help manage fin and tail rot, skin ulcers, infected wounds, red patches, and other bacterial concerns when used as directed.
Made in the United States
Fix Flex is manufactured in the United States by Aqua Soma Labs, with clear strength labeling and expiration information on each bottle.
Two Strengths to Match Your Tank
Choose 250 mg capsules for smaller treatment systems or 500 mg capsules for larger water volumes while following the product label.
Consistent Capsules
Each capsule provides a consistent amount of cephalexin, making aquarium-volume calculations easier across quarantine tanks and larger treatment systems.
Easy to Prepare
Capsules can be opened and the powder mixed with aquarium water, helping distribute the treatment evenly while limiting unnecessary handling of stressed fish.
Freshwater, Saltwater & Aviary Setups
Fix Flex may be used in properly prepared freshwater or marine hospital tanks and in veterinarian-directed treatment plans for pigeons and other ornamental birds.
Good for Hospital Tanks and Quarantine
A separate treatment system protects the main aquarium's biological filtration and reduces unnecessary exposure of healthy tank mates and sensitive invertebrates.
Usage Guidelines & Instructions
Set Up a Separate Treatment Area
Move affected fish to a dedicated hospital or quarantine tank before treatment.
Where practical, birds receiving veterinarian-directed treatment should be separated into an appropriate treatment enclosure.
Separation helps protect healthy animals and allows more accurate treatment and observation.
Choose the Right Strength
Fix Flex is available in 250 mg and 500 mg capsule strengths.
Select the strength that matches the treatment-tank water volume or the instructions provided by a qualified professional.
Do not increase the amount, shorten the interval, or extend treatment beyond the label directions.
Directions for Fish Aquariums
Add one dissolved 250 mg dose per 10 gallons or approximately 38 litres of treatment water.
Open the capsule, stir the powder into a clean cup of aquarium water, and distribute the prepared solution evenly throughout the hospital tank.
Repeat every 24 hours for 5 to 10 days, performing a partial water change between treatments.
Discontinue treatment and consult an aquatic veterinarian if no improvement is seen within five days.
Use in Pet Birds Under Veterinary Guidance
Only administer cephalexin to pigeons and other non-food pet birds under the direction of an avian veterinarian.
The veterinarian should determine the correct amount according to the bird's species, weight, condition, frequency, and treatment duration.
Capsule contents may be mixed with soft food or drinking water only as specifically instructed.
Maintain Water Quality & Complete Treatment
Perform partial water changes when needed between treatments to keep ammonia and nitrite low.
Maintain stable temperature and strong aeration throughout the treatment period.
Complete the full label-directed treatment unless a veterinarian advises otherwise.
Seek professional guidance if symptoms become worse or fail to improve.
Fix Flex Amounts by Aquarium Size
| Tank volume | Cephalexin per use | 250 mg capsules | 500 mg capsules |
|---|---|---|---|
| 10 gallons (38 L) | 250 mg | 1 capsule | Use the 250 mg strength |
| 20 gallons (76 L) | 500 mg | 2 capsules | 1 capsule |
| 30 gallons (114 L) | 750 mg | 3 capsules | 1 capsule plus one 250 mg capsule |
| 40 gallons (151 L) | 1,000 mg | 4 capsules | 2 capsules |
| 55 gallons (208 L) | Approximately 1,375 mg | 5 to 6 capsules | Approximately 3 capsules |
What to Expect During Treatment
Days 1 to 2
Fish may hide, eat less, or produce slightly cloudy treatment water. Maintain strong aeration and continue monitoring water quality.
Days 3 to 5
Look for sores and red patches that stop spreading, returning appetite, improved activity, and steadier breathing.
Days 5 to 10
Complete the recommended treatment even when improvement appears. After treatment, perform a partial water change and restore activated carbon.
What You Need for Treatment
Prepare the following supplies before the first treatment:
- A separate hospital or quarantine tank
- A suitable aquarium heater
- An air stone or established sponge filter
- An ammonia and nitrite test kit
- A suitable water conditioner or dechlorinator
- A small net for gentle fish transfer
- A clean cup for mixing each treatment
Pro Tip: Quarantine affected fish and birds away from healthy companions whenever practical. A dedicated treatment setup with stable temperature, strong aeration, and no substrate makes observation and water changes easier.
How Fix Flex Works
Fix Flex supplies cephalexin as the active ingredient at a strength of 250 mg or 500 mg per capsule.
Cephalexin works against a range of susceptible Gram-positive bacteria and some Gram-negative species that may affect the skin, fins, wounds, and soft tissues of ornamental fish and non-food pet birds.
In practical terms, it helps slow or stop the growth of susceptible bacteria so the animal has a better opportunity to recover when the underlying condition is bacterial.
Each hard capsule contains cephalexin powder together with standard inactive ingredients that support capsule stability and help the contents disperse when mixed into aquarium water.
Administration to birds should follow the exact method and amount provided by an avian veterinarian.
Safety and Tank Notes
When used as directed, Fix Flex generally causes no problems in ornamental aquarium fish and non-food pet birds.
Incorrect amounts, unnecessarily prolonged use, or repeated antibacterial treatment may increase the risk of unwanted reactions and bacterial resistance.
Fish
Cephalexin treatment may cause temporary hiding, mild treatment-water cloudiness, reduced activity, or appetite loss.
If severe distress appears, including rapid gill movement, surface gasping, loss of balance, or remaining on the bottom, stop treatment, improve aeration, perform an appropriate water change, and seek aquatic veterinary advice.
Birds
Possible reactions may include reduced appetite, loose or changed droppings, and lethargy, particularly when the amount is too high or the bird is sensitive.
If a bird becomes fluffed up, inactive, has difficulty breathing, or stops eating, discontinue treatment and contact an avian veterinarian.
Invertebrates
Do not use Fix Flex in display aquariums containing shrimp, snails, corals, or other sensitive invertebrates whenever a separate hospital tank is available.
Strong antibacterial treatment may harm sensitive species or disrupt the aquarium ecosystem.
Safe Use in Your System
Remove activated carbon and switch off UV sterilization during treatment.
Monitor ammonia, nitrite, temperature, and oxygen levels closely.
Do not combine Fix Flex with other treatments unless specifically advised by a qualified veterinarian.
Important Safety Warning
Fix Flex is intended for ornamental aquarium fish and non-food pet birds only. It is not intended for animals raised for food.
Store the capsules in their original container in a cool, dry location protected from direct sunlight, excessive heat, and moisture.
Keep the container tightly closed and out of reach of children and animals.
Always follow the current product-label directions.
Shipping & Returns
Shipping Policy
Orders ship from our United States warehouse within one business day through USPS or UPS.
Same-day dispatch may be available for qualifying orders placed before 1:30 p.m. CT, Monday through Friday.
Shipping prices and estimated delivery times are calculated at checkout.
Review Shipping Policy →Refund Policy
If there is an issue with your order, eligible products may be returned or exchanged within 30 days according to the current store guidelines.
Review the complete refund policy before returning any product.
Review Refund Policy →Frequently Asked Questions
What is Fix Flex used for in fish and birds?
Fix Flex contains cephalexin and is used for certain bacterial concerns affecting ornamental aquarium fish, including fin and tail rot, skin ulcers, infected wounds, red patches, pop-eye, and soft-tissue infections.
In non-food pet birds, use should occur only under avian veterinary guidance.
What is the difference between Fish Flex and Fix Flex?
Fix Flex is the current Aqua Soma Labs replacement for discontinued Fish Flex products. It provides cephalexin in familiar 250 mg and 500 mg capsule strengths with updated packaging.
Is Fix Flex a replacement for Fish Flex Forte?
Yes. The 500 mg Fix Flex strength is presented as the replacement for older Fish Flex Forte 500 mg products.
Is Fix Flex the same as Aqua Ceph or Aqua Flex?
Fix Flex is the updated Aqua Soma Labs cephalexin product replacing older Aqua Ceph and Aqua Flex names in familiar 250 mg and 500 mg strengths.
Is Fish Flex the same as fish cephalexin 500 mg?
The Fix Flex 500 mg option contains 500 mg of cephalexin per capsule. A separate 250 mg strength is also available.
Where can I buy cephalexin for fish online?
Fix Flex 250 mg and 500 mg capsules can be ordered through this online store in 30-count or 100-count bottles and shipped according to the current store shipping policy.
How do I know if my fish might need cephalexin?
Possible bacterial signs include frayed fins, ulcers, infected wounds, red or cloudy body areas, swelling, pop-eye, dropsy, appetite loss, and listless behavior.
Similar signs may also result from poor water quality, parasites, fungal conditions, injury, or other causes, so professional assessment is recommended when the diagnosis is uncertain.
How do I choose between 250 mg and 500 mg capsules?
Select the strength according to the actual water volume of the treatment tank. The supplied guideline uses 250 mg per 10 gallons, meaning one 500 mg capsule corresponds to approximately 20 gallons.
Can I use Fix Flex in my main community or reef tank?
A separate hospital tank is preferred. This reduces exposure of healthy fish and sensitive invertebrates and helps protect the display aquarium's biological filtration.
Does Fix Flex work in saltwater aquariums?
Fix Flex is presented for use in properly prepared freshwater and saltwater treatment systems. A separate hospital tank is especially important for marine systems containing corals or invertebrates.
How long should I treat with Fix Flex?
The supplied instructions describe treatment every 24 hours for 5 to 10 days, with partial water changes between treatments.
Discontinue treatment and seek professional advice if no improvement is seen within five days.
Can Fix Flex be used for pet birds?
Fix Flex may be considered for non-food pet birds only under avian veterinary guidance. The veterinarian must determine the amount, administration method, frequency, and duration.
Can I use Fix Flex for my dog or cat?
No. This product is labeled for ornamental aquarium fish and non-food pet birds. It is not intended for dogs, cats, humans, or food-producing animals.
Will Fix Flex harm beneficial aquarium bacteria?
Antibacterial treatments may disrupt beneficial biological filtration. Use a separate treatment tank whenever possible and monitor ammonia and nitrite closely.
Can I combine Fix Flex with other fish treatments?
Do not combine Fix Flex with other antibacterial or aquarium treatments unless a qualified veterinarian specifically recommends the combination.
How quickly should I see improvement?
Improvement may appear within three to five days through sores that stop spreading, improved appetite, steadier breathing, and increased activity.
Stop and seek professional guidance if the animal worsens or no improvement appears by day five.
Can Fix Flex treat fungal, viral, or parasitic infections?
Fix Flex is an antibacterial product. It should not be expected to treat fungal, viral, or parasitic conditions unless a professional has identified a separate appropriate reason for its use.
How should I store and dispose of Fix Flex capsules?
Store capsules tightly closed in their original container in a cool, dry place protected from sunlight and moisture.
Follow the current label and applicable local requirements when disposing of unused capsules, treatment water, or filter media. Avoid releasing concentrated treatment into natural waterways.
What is fish cephalexin?
Fish cephalexin is a commonly used search term for cephalexin capsules labeled for ornamental aquarium fish. Fix Flex is offered in 250 mg and 500 mg capsule strengths.
How much Fix Flex should I use per gallon?
The supplied label reference is 250 mg per 10 gallons, approximately 25 mg per gallon. Always follow the current bottle label and dose according to the actual treatment-tank water volume.
More Fish & Bird Treatments
Fix Mox (Amoxicillin) 250/500 mg
A treatment for fin rot, dropsy, ulcers, and other bacterial concerns in ornamental fish. Available in 30-count and 100-count capsules.
Shop Fix Mox →Fix Zole (Metronidazole) 250/500 mg
Targets certain anaerobic organisms and protozoa associated with Hexamita and hole-in-the-head concerns. Available in 60-count bottles.
Shop Fix Zole →Fix Doxy (Doxycycline) 100 mg
A treatment for columnaris, respiratory concerns, and Mycoplasma-related problems in ornamental fish and non-food pet birds.
Shop Fix Doxy →Fix Zithro (Azithromycin) 250 mg
A treatment for fin rot, columnaris, gill disease, and veterinarian-directed avian respiratory concerns.
Shop Fix Zithro →Fix Cin (Clindamycin) 150 mg
A treatment for certain Gram-positive bacterial concerns, including skin and soft-tissue problems in ornamental fish.
Shop Fix Cin →Fix Sulfa (SMZ/TMP) 960 mg
A treatment used for a range of bacterial concerns affecting ornamental aquarium fish.
Shop Fix Sulfa →Fix Pen (Penicillin) 500 mg
A treatment for certain Gram-positive bacterial concerns in ornamental fish and non-food pet birds.
Shop Fix Pen →Fix Flox (Ciprofloxacin) 500 mg
A treatment for certain Gram-negative bacterial concerns including fin rot, ulcers, columnaris, and septicemia.
Shop Fix Flox →Browse All Treatments
Explore our complete Fish & Bird Treatments Collection for additional Fix line products and related care options.
Explore the Collection →Guides and Care Tips
Visit the Fish & Bird Care Blog for practical guides, aquarium water-care information, and treatment tips.
Visit the Blog →Transparency & Verification
How Product Information Is Verified
Who is responsible for this page: The store editorial team responsible for reviewing and maintaining product information.
Verification snapshot: This page is written from the current product label for this item and reviewed for accuracy and consistency before publishing.
How We Verify Product Information
Label-First Accuracy
Directions, treatment duration, storage information, and warnings are taken from the current product label.
Specification Validation
Key details such as the active ingredient, capsule strengths, bottle counts, and manufacturer information are cross-checked against available product specifications.
Consistency Checks
Product content is reviewed for consistent strengths, directions, safety language, and storage details throughout the page.
Updates
Pages are updated when product labels, packaging, capsule counts, manufacturer details, or directions change.
See something that does not match the product you received? Please contact us so the information can be reviewed and updated.
Fish Sulfa Forte | Sulfa Antibiotic for Aquarium Fish
Regular price $39.99 Save $-39.99Fish Sulfa Forte (Fix Sulfa) Tablets, 960 mg
Fish Sulfa (Fix Sulfa) SMZ/TMP 960 mg is an antibacterial treatment for ornamental aquarium fish.
Each scored tablet combines sulfamethoxazole 800 mg with trimethoprim 160 mg. Aquarium keepers use this dual-ingredient combination to help manage suspected bacterial problems in freshwater and saltwater treatment systems.
In older aquarium listings and hobby forums, this SMZ/TMP product may also be called Fish Sulfa, Fish Sulfa Forte, FISHBIOTIC SMZ/TMP, Aqua Sulfa, or Aqua-SMZ/TMP.
Fix Sulfa is the current-production Aqua Soma Labs replacement for the discontinued Thomas Labs Fish Sulfa Forte.
Aquarium keepers commonly use this combination when fish show symptoms associated with fin and tail rot, columnaris or cotton-wool-type patches, skin sores, ulcer-like lesions, bacterial hemorrhagic septicemia, pop-eye, cloudy eyes, and body-slime concerns.
These signs may involve susceptible bacteria such as Aeromonas, Vibrio, or Streptococcus.
SMZ/TMP combines two active ingredients that work together to help slow the growth of certain bacteria.
Used as directed, sulfamethoxazole and trimethoprim work best alongside stable water parameters, strong aeration, clean treatment water, reduced stress, and appropriate aquarium husbandry.
Fix Sulfa comes as a consistent 960 mg scored tablet that can be divided, crushed, and dissolved.
It is available in bottles containing 30 or 60 tablets with clearly printed expiration dates, allowing aquarium keepers to choose a suitable quantity for one quarantine tank or a multi-tank fish room.
Begin treatment at the first signs of bacterial stress and use a hospital or quarantine tank whenever practical.
Fish Symptoms Aquarists Treat With Fix Sulfa
- Fin and tail rot with frayed or deteriorating fins
- Skin sores, ulcer-like lesions, and red streaks
- Pop-eye or bulging eyes
- Cloudy eyes
- Columnaris with a cotton-wool-type appearance
- Bacterial hemorrhagic septicemia
- Body-slime concerns associated with susceptible bacteria
- Lethargy, rapid breathing, or appetite loss that does not resolve after water-quality correction
Same-day dispatch: Qualifying orders placed before 1:30 p.m. CT, Monday through Friday, ship from our United States warehouse through USPS or UPS.
Fish Sulfa Forte vs Fix Sulfa: What Changed?
If you previously purchased Thomas Labs Fish Sulfa Forte, FISHBIOTIC SMZ/TMP, Aqua Sulfa, or Aqua-SMZ/TMP, here is what has changed and what remains the same.
Same SMZ/TMP Combination
Fix Sulfa contains sulfamethoxazole 800 mg and trimethoprim 160 mg per tablet, providing a combined strength of 960 mg.
Updated Fix Branding
Aqua Soma Labs produces Fix Sulfa as the current replacement for discontinued Fish Sulfa Forte and other older aquarium SMZ/TMP products.
Same Scored Tablet Form
Each tablet provides a consistent 960 mg total strength and can be divided, crushed, and dissolved according to the aquarium-water volume.
Flexible Bottle Sizes
Choose between 30-count and 60-count bottles for short treatment plans, quarantine systems, or larger multi-tank setups.
Benefits of Fix Sulfa for Fish
Dual-Action SMZ/TMP Combination
Fix Sulfa pairs sulfamethoxazole and trimethoprim, a combination aquarium keepers use to help manage certain bacterial concerns in ornamental fish.
Made in the United States
Fix Sulfa is manufactured in the United States by Aqua Soma Labs as the current-production replacement for discontinued Fish Sulfa Forte products.
Support for Common Aquarium Problems
Aquarium keepers may choose Fish Sulfa tablets for fin and tail rot, columnaris-type patches, cotton-wool-type signs, ulcers, pop-eye, cloudy eyes, and persistent bacterial symptoms.
External and Internal Bacterial Signs
SMZ/TMP may be used in a hospital tank for visible sores and fin damage or when lethargy and appetite loss occur together with suspected bacterial stress.
Consistent 960 mg Tablet Strength
Each scored tablet provides a predictable amount of sulfamethoxazole and trimethoprim, helping aquarium keepers plan repeatable amounts for different water volumes.
Intended for Ornamental Fish
Fix Sulfa is formulated and labeled for ornamental aquarium fish and provides a countable tablet format for treatment-tank use.
Helpful for Hospital Tanks
A separate hospital or quarantine tank allows closer observation, more accurate treatment, and reduced exposure of healthy tank mates.
Usage Guidelines & Instructions
These steps follow the supplied Fix Sulfa 960 bottle-label directions for SMZ/TMP use in ornamental aquarium fish.
Quick Usage Summary
Dissolve one tablet and add it for every 40 gallons or approximately 151 litres of treatment water.
Repeat every 24 hours with a partial water change between treatments for 5 to 10 days.
Discontinue use if no improvement is noted after five days.
Before You Dose
Measure the Actual Water Volume
Calculate the real volume of water being treated rather than relying only on the aquarium's advertised capacity.
Account for substrate, rocks, decorations, equipment, and the actual fill level.
Use a Hospital or Quarantine Tank
Treat affected fish in a separate system whenever practical for better control and closer observation.
Remove Carbon and Turn Off UV
Remove activated carbon and other chemical filtration media before treatment.
Switch off ultraviolet sterilization because these systems may reduce treatment availability in the water.
Increase Aeration
Increase surface agitation and aeration while keeping the treatment-tank temperature stable.
Directions for Use
Dissolve and Add the Treatment
Fully dissolve one tablet in a small cup of aquarium water.
Add the dissolved mixture evenly throughout the treatment tank at a rate of one tablet per 40 gallons or approximately 151 litres.
Repeat Every 24 Hours
Repeat treatment once every 24 hours.
Perform a partial water change between treatments to maintain suitable water quality.
Complete Treatment and Monitor Progress
Continue treatment for 5 to 10 days according to the current bottle label.
Monitor appetite, swimming behavior, breathing, fin condition, sores, and signs of stress.
Discontinue use if no improvement is noted after five days.
If fish appear worse or develop severe stress, stop treatment and seek aquatic veterinary advice.
Post-Treatment Cleanup
After treatment is complete, perform a partial water change and resume normal filtration.
Replace activated carbon or other chemical media if they were removed.
Continue monitoring ammonia, nitrite, temperature, and fish behavior for several days.
Fix Sulfa Amounts by Aquarium Size
| Tank volume | Fix Sulfa 960 amount | How to measure |
|---|---|---|
| 10 gallons (38 L) | ¼ tablet | Divide the scored tablet or add one-quarter of a fully dissolved tablet |
| 20 gallons (76 L) | ½ tablet | Divide the scored tablet or add one-half of a fully dissolved tablet |
| 40 gallons (151 L) | 1 tablet | Dissolve one complete tablet according to the label standard |
| 80 gallons (303 L) | 2 tablets | Dissolve two complete tablets |
| 120 gallons (454 L) | 3 tablets | Dissolve three complete tablets |
What to Expect During Treatment
Days 1 to 2
Fish may hide, eat less, or produce slightly cloudy treatment water. Maintain the treatment schedule and keep aeration strong.
Days 3 to 5
Look for sores and red patches that stop spreading, returning appetite, improved activity, and steadier breathing.
Days 5 to 10
Complete the recommended treatment period. After treatment, perform a partial water change and restore activated carbon if normally used.
What You Need for Treatment
- A separate hospital or quarantine tank
- A suitable aquarium heater
- An air stone or established sponge filter
- An ammonia and nitrite test kit
- A suitable water conditioner or dechlorinator
- A small net for gentle transfer
- A clean cup for dissolving and measuring the treatment
Pro Tip: Hospital-tank treatment helps protect the display aquarium, keeps the amount consistent, and makes it easier to maintain ammonia and nitrite at safe levels during recovery.
How Fix Sulfa Works
Each Fix Sulfa tablet combines sulfamethoxazole 800 mg with trimethoprim 160 mg, providing a total SMZ/TMP strength of 960 mg.
When dissolved and added to aquarium water according to the label, the two active ingredients work together to help slow the growth of certain susceptible bacteria.
This combination is commonly used by aquarium keepers for suspected bacterial concerns involving fins, skin, sores, ulcers, eyes, and systemic signs in ornamental freshwater and saltwater fish.
Each tablet also contains standard inactive ingredients that help hold the tablet together, support storage stability, and allow the contents to disperse when dissolved in water.
Safety and Tank Notes
Individual fish may respond differently to treatment. Follow the current label and monitor fish and water quality closely throughout the treatment period.
Possible Side Effects in Fish
Possible temporary reactions include reduced appetite, mild lethargy, hiding behavior, and occasional water cloudiness.
If fish develop rapid gill movement, surface gasping, loss of balance, or remain on the bottom, stop treatment, increase aeration, and seek aquatic veterinary advice.
Stop Treatment If
Stop treatment when fish show severe stress, worsening symptoms, rapid gill movement, surface gasping, loss of balance, or a serious decline in activity.
Increase aeration immediately and consult an aquatic veterinarian if the signs do not stabilize.
Water Quality and Biofilter Awareness
Keep aeration strong and monitor ammonia and nitrite closely.
Perform partial water changes when necessary to keep the treatment system stable.
Filtration During Treatment
Remove activated carbon and other chemical filtration media before treatment.
Switch off ultraviolet sterilization and resume normal filtration only after treatment is complete.
Invertebrates and Display Tanks
If the aquarium contains shrimp, snails, corals, or other sensitive invertebrates, treat affected fish in a separate hospital tank whenever practical.
Do Not Mix Treatments
Avoid combining Fix Sulfa with other aquarium treatments unless the product label explicitly allows it or an aquatic veterinarian recommends it.
Important Warnings & Precautions
Aquarium use only: Fix Sulfa is intended for ornamental aquarium fish only.
Not for food fish: Do not use this product on fish raised for human consumption.
Handling: Avoid contact with the dissolved treatment. Wash your hands after handling and use suitable gloves when needed. Keep the tablet contents and dissolved product away from the skin and eyes.
Storage: Keep the container tightly closed in a cool, dry location protected from direct sunlight and moisture.
Keep out of reach of children and animals. Check the expiration date and do not use expired tablets.
Discontinue if no improvement: If no improvement is noted after five days, stop treatment and re-evaluate the diagnosis or seek aquatic veterinary advice.
Shipping & Returns
Shipping Policy
Orders ship from our United States warehouse within one business day through USPS or UPS.
Qualifying orders placed before 1:30 p.m. CT, Monday through Friday, may ship the same business day.
Shipping rates and estimated delivery times are calculated at checkout.
Review Shipping Policy →Refund Policy
If there is an issue with your order, eligible products may be returned or exchanged within 30 days according to the current store guidelines.
Review the complete refund policy before returning any product.
Review Refund Policy →Frequently Asked Questions
What is Fix Sulfa used for?
Fix Sulfa is an SMZ/TMP antibacterial treatment for certain suspected bacterial problems in ornamental aquarium fish, including fin and tail rot, ulcers, columnaris-type signs, pop-eye, cloudy eyes, red streaking, and systemic bacterial stress.
What is Fish Sulfa Forte?
Fish Sulfa Forte was an aquarium SMZ/TMP product containing sulfamethoxazole and trimethoprim. Fix Sulfa is the current Aqua Soma Labs replacement in the same combined 960 mg strength.
What is the difference between Fish Sulfa Forte and Fix Sulfa?
Fix Sulfa uses the same combination of sulfamethoxazole 800 mg and trimethoprim 160 mg associated with older Fish Sulfa Forte products. The main changes are the manufacturer, branding, packaging, and current production.
Is Fix Sulfa a replacement for Aqua-SMZ/TMP?
Fix Sulfa is presented as the current Aqua Soma Labs replacement for older Aqua Sulfa and Aqua-SMZ/TMP aquarium products.
Where can I buy SMZ/TMP fish tablets online?
Fix Sulfa 960 mg tablets can be ordered through this online store in 30-count or 60-count bottles and shipped according to the current store shipping policy.
What are the active ingredients in each tablet?
Each scored tablet contains sulfamethoxazole 800 mg and trimethoprim 160 mg, providing a combined strength of 960 mg.
What is the Fix Sulfa amount for fish?
The supplied label direction is one 960 mg tablet per 40 gallons or approximately 151 litres of treatment water.
How much Fix Sulfa should I use per gallon?
One tablet per 40 gallons equals approximately 24 mg of combined sulfamethoxazole and trimethoprim per gallon. Follow the current bottle label rather than relying only on a calculated per-gallon amount.
How long should I treat with Fix Sulfa?
The supplied instructions describe treatment every 24 hours for 5 to 10 days, with a partial water change between treatments.
Discontinue treatment if no improvement is noted after five days.
How soon should I see improvement?
Improvement may appear within three to five days through sores that stop spreading, improved appetite, steadier breathing, and increased activity.
Stop treatment and seek professional guidance if fish worsen or no improvement appears by day five.
Should I treat in the main tank or a hospital tank?
A separate hospital or quarantine tank is preferred. This provides better treatment control, protects healthy tank mates, and reduces disturbance to the display aquarium.
Do I need to remove carbon or turn off UV?
Remove activated carbon and other chemical filtration media and switch off ultraviolet sterilization during treatment because these systems may reduce treatment availability in the water.
Will Fix Sulfa harm beneficial aquarium bacteria?
Antibacterial treatment may disturb biological filtration. Use a separate treatment system when possible and monitor ammonia and nitrite closely.
Can Fix Sulfa treat fungal, viral, or parasitic infections?
Fix Sulfa is an antibacterial treatment. It should not be expected to treat fungal, viral, or parasitic conditions.
Is Fix Sulfa safe for betta fish and small aquariums?
Small treatment tanks require careful measurement. Because each tablet is scored, it may be divided, or a complete tablet may be dissolved in a measured amount of water and the correct fraction added. Always follow the current bottle label.
Does Fix Sulfa work in saltwater aquariums?
Fix Sulfa is presented for ornamental fish in freshwater and saltwater treatment systems. Use a separate hospital tank when the display aquarium contains corals or sensitive invertebrates.
Can I combine Fix Sulfa with other fish treatments?
Do not combine Fix Sulfa with other treatments unless the label specifically permits the combination or an aquatic veterinarian recommends it.
What if my fish are not improving?
Discontinue treatment if no improvement is noted after five days. Re-evaluate the water quality and diagnosis and seek aquatic veterinary advice.
What should I do after finishing treatment?
Perform a partial water change, resume normal filtration, restore activated carbon or chemical media, and continue monitoring ammonia, nitrite, and fish behavior for several days.
How should I store and dispose of Fix Sulfa tablets?
Store tablets tightly closed in the original container in a cool, dry location protected from sunlight and moisture.
Follow the product label and applicable local requirements when disposing of unused tablets, treatment water, or filter media. Avoid releasing concentrated treatment into natural waterways.
Bottom Line
Fix Sulfa is an SMZ/TMP 960 mg antibacterial treatment containing sulfamethoxazole 800 mg and trimethoprim 160 mg for bacterial concerns in ornamental aquarium fish.
It is the current-production replacement for discontinued Thomas Labs Fish Sulfa Forte.
Dose according to water volume at one tablet per 40 gallons or approximately 151 litres, repeat every 24 hours with a partial water change between treatments, and continue for 5 to 10 days according to the current bottle label.
Reassess treatment at day five and discontinue use if no improvement is noted.
Fix Sulfa does not treat fungal, viral, or parasitic conditions and is intended only for ornamental aquarium fish, not animals raised for food.
Choose the bottle size that fits your aquarium setup, or compare the additional Fix line products below.
More Fish & Bird Treatments
Fix Mox (Amoxicillin) 250/500 mg
A treatment for fin rot, dropsy, ulcers, and other bacterial concerns in ornamental fish. Available in 30-count and 100-count capsules.
Shop Fix Mox →Fix Zole (Metronidazole) 250/500 mg
Targets certain anaerobic organisms and protozoa associated with Hexamita and hole-in-the-head concerns. Available in 60-count bottles.
Shop Fix Zole →Fix Doxy (Doxycycline) 100 mg
A treatment for columnaris, respiratory concerns, and Mycoplasma-related problems in ornamental fish and non-food pet birds.
Shop Fix Doxy →Fix Zithro (Azithromycin) 250 mg
A treatment for fin rot, columnaris, gill disease, and veterinarian-directed avian respiratory concerns.
Shop Fix Zithro →Fix Cin (Clindamycin) 150 mg
A treatment for bacterial skin and soft-tissue concerns in ornamental fish.
Shop Fix Cin →Fix Pen (Penicillin) 500 mg
A penicillin treatment for bacterial concerns in ornamental fish and non-food pet birds.
Shop Fix Pen →Fix Flex (Cephalexin) 250/500 mg
A treatment for fin rot, ulcers, infected wounds, and bacterial skin concerns in ornamental fish and non-food pet birds.
Shop Fix Flex →Fix Flox (Ciprofloxacin) 500 mg
A treatment for bacterial concerns including fin rot, ulcers, columnaris-type patches, and septicemia in ornamental fish.
Shop Fix Flox →Browse All Treatments
Explore the complete Fish & Bird Treatments Collection for additional Fix line products and related treatment options.
Explore the Collection →Guides and Care Tips
Visit the Fish & Bird Care Blog for practical aquarium guides, water-care information, and treatment tips.
Visit the Blog →Transparency & Verification
How Product Information Is Verified
Who is responsible for this page: The store editorial team responsible for reviewing and maintaining product information.
Verification snapshot: This page is written from the current product label for this item and reviewed for accuracy and consistency before publishing.
How We Verify Product Information
Label-First Accuracy
Directions, treatment duration, storage information, and warnings are taken from the current product label.
Specification Validation
Active ingredients, tablet strengths, bottle counts, and manufacturer details are cross-checked against available product specifications.
Consistency Checks
Product content is reviewed for consistent directions, strengths, storage information, and safety language throughout the page.
Updates
Pages are updated when product labels, packaging, bottle counts, manufacturer details, or directions change.
See something that does not match the product you received? Please contact us so the information can be reviewed and updated.
Fish Doxy 100mg (Doxycycline) | Fish Antibiotic
Regular price $43.99 Save $-43.99Fix Doxy (Fish Doxy) Doxycycline Tablets - 100 mg
Fix Doxy delivers doxycycline hyclate 100 mg per tablet for ornamental aquarium fish and non-food pet birds, made by Aqua Soma Labs. It is used when bacterial problems appear, such as fin and tail rot, columnaris (often seen as cotton wool disease), bacterial hemorrhagic septicemia, and other internal bacterial infections in freshwater and saltwater aquariums.
It is also chosen for racing pigeons and other pet birds during respiratory infections, mycoplasmosis (mycoplasma), or suspected chlamydiosis, also known as parrot fever, psittacosis, or ornithosis.
If you used to buy the discontinued Thomas Labs Fish Doxy, Aqua Doxy, or older Bird Biotic, Fix Doxy is the online replacement. It supplies the same doxycycline strength in bottles of 30 or 60 tablets with fresh expiration dates, and it is a straightforward option when you need doxycycline for birds or a fish doxycycline product to buy online.
Use Fix Doxy when you notice early signs of bacterial stress in your fish or pet birds. Common symptoms differ between species, so check the lists below to identify what to watch for.
Fish-Specific Symptoms
- Clamped or frayed fins (fin and tail rot)
- Slime disease, mouth fungus, or mouth rot
- Columnaris (cotton wool disease)
- Red or cloudy patches on the body
- Bacterial hemorrhagic septicemia
- Gill disease or labored gill movement
- Loss of appetite or hiding behavior
Bird-Specific Symptoms
- Respiratory infections: sneezing, wheezing, or nasal discharge
- Mycoplasmosis (mycoplasma)
- Chlamydiosis, ornithosis, psittacosis, or parrot fever
- Pasteurellosis, commonly seen in pigeons
- Fluffed-up feathers, lethargy, or inactivity
- Eye infections or persistent loss of appetite
- Changes in droppings or vocalization
Addressing potential bacterial issues early with doxycycline, together with good water quality and advice from an aquatic or avian professional when available, helps your fish and birds maintain a stable, healthy aquarium or aviary.
Order online and ship directly from our U.S. warehouse. Fix Doxy doxycycline 100 mg tablets are available to buy online with same-day dispatch on orders placed before 1:30 p.m. CT, Monday through Friday.
Fish Doxy vs Fix Doxy: What Changed?
If you used to buy Fish Doxy, Aqua Doxy, or Bird Biotic from Thomas Labs, here is what stayed the same and what is different with Fix Doxy from Aqua Soma Labs.
Same Doxycycline
Fix Doxy delivers the same doxycycline hyclate 100 mg per tablet that was used in the original Fish Doxy and Bird Biotic products.
New Manufacturer
Fix Doxy is made by Aqua Soma Labs, replacing Thomas Labs, which discontinued its Fish Doxy and Bird Biotic lines.
Same Tablet Form
100 mg tablets with the same dosing style of one tablet per 15 gallons, so switching from Fish Doxy to Fix Doxy requires no changes to your routine.
Updated Packaging & Labeling
New bottle design and labeling under the Fix brand, with the same doxycycline formula and fresh expiration dates.
Benefits of Fix Doxy for Fish & Birds
Targets Common Bacterial Problems
Helps manage common bacterial problems such as fin and tail rot, columnaris, gill disease, septicemia, internal bacterial infections, and avian respiratory infections caused by certain Gram-positive and Gram-negative bacteria in both freshwater and saltwater aquariums.
Made in the United States
Fix Doxy is manufactured by Aqua Soma Labs and ships from a U.S. warehouse with fresh expiration dates, so you receive a recently made product ready for your tank or aviary.
One Solution for Fish & Birds
Fix Doxy is formulated for ornamental aquarium fish and non-food pet birds, so one doxycycline product covers tanks and aviaries. Use it for individual treatment or a whole flock as appropriate.
Fixed 100 mg Tablets
Each tablet delivers a fixed 100 mg doxycycline amount. These fish doxycycline tablets make it easier to follow the charts and repeat treatments accurately across different tank volumes or bird sizes.
Flexible Use in Tanks & Feed
Tablets are water-soluble and easy to crush, so you can dissolve them in a hospital or quarantine tank, or mix them with food or drinking water as directed. This helps when you need to treat sensitive fish or birds.
Available in 30-Count and 60-Count Bottles
Choose a 30-count bottle for a single treatment or a 60-count bottle for larger tanks, multiple birds, or repeat treatments, so you always have doxycycline on hand when needed.
Direct Fish Doxy & Bird Biotic Replacement
Fix Doxy replaces the discontinued Fish Doxy from Thomas Labs, Aqua Doxy, and Bird Biotic products. It delivers the same doxycycline hyclate 100 mg per tablet that hobbyists and breeders used before those lines were discontinued.
Usage Guidelines & Instructions
Prepare a Separate Treatment Area
For fish, set up a hospital or quarantine tank with clean, dechlorinated water so you can treat without disturbing the main display tank or its biofilter.
Any aquarium doxycycline treatment works best in a separate tank, so remove activated carbon, resins, and UV sterilizers during dosing, as they can strip doxycycline from the water.
Calculate and Give the Dose
Fish: Check the dosing instructions on your Fix Doxy bottle. Label directions for 100 mg tablets typically call for one tablet, or 100 mg, per 15 gallons or 57 litres of water, repeated every 24 hours for several days.
Pre-dissolve the tablet in a small cup of tank water, then add it evenly around the treatment tank.
Birds: For companion birds, the amount is based on the bird's weight or the volume of treated drinking water. Crush the tablet and mix with soft food or a measured amount of drinking water only as directed on the packaging or by an avian veterinarian, making sure the bird receives the full intended amount.
Monitor Progress and Water Quality
Watch appetite, breathing, activity level, and fin or feather condition every day. If symptoms worsen or no improvement is seen after several days, contact a veterinarian.
For fish, perform partial water changes between doses if water quality declines, then re-dose for the new water volume.
Continue treatment for the full number of days recommended on the label, usually around 5 to 10 days, unless your veterinarian advises otherwise, and never exceed label directions.
Fix Doxy Amounts by Aquarium Size
| Tank volume | 100 mg tablets per use |
|---|---|
| 15 gallons (57 L) | 1 tablet |
| 30 gallons (114 L) | 2 tablets |
| 45 gallons (170 L) | 3 tablets |
| 60 gallons (227 L) | 4 tablets |
| 75 gallons (284 L) | 5 tablets |
What to Expect During Treatment
Days 1 to 2
Fish may hide or eat less, and the water can look slightly discolored. This is normal early on. Keep dosing on schedule and keep aeration strong.
Days 3 to 5
Look for signs it is working: sores and red patches stop spreading, appetite starts to return, and breathing steadies.
Days 5 to 10
Even if the fish are improving, finish the full number of days so the infection does not return. Afterward, run a partial water change and put activated carbon back in to clear leftover doxycycline.
What You Need for Treatment
A little setup before the first dose saves trouble later.
- A separate hospital or quarantine tank, so you are not treating the whole display
- A heater and an air stone or sponge filter for steady temperature and strong aeration
- An ammonia and nitrite test kit to keep tabs on water quality
- A dechlorinator for water changes between doses
- A small net and a clean cup for gentle transfer and for dissolving each tablet
Pro Tip: Keep a few extra Fix Doxy tablets on hand so you always have them ready at the first sign of bacterial stress. A quarantine tank with a heater and sponge filter makes treatment faster and protects your main system.
How Fix Doxy Works
Fix Doxy uses doxycycline hyclate 100 mg per tablet to help control certain Gram-positive and Gram-negative bacteria linked with fin and tail rot, mouth rot, columnaris, gill disease, septicemia, and avian respiratory infections.
The tablets dissolve readily in aquarium water, and they can also be crushed and mixed with soft food or drinking water, which spreads the dose evenly through a treatment tank or across a flock.
Safety and Tank Notes
When used as directed, Fix Doxy usually causes no problems in ornamental fish and pet birds. As with any doxycycline product, incorrect amounts or prolonged use can increase the risk of side effects.
Fish
Doxycycline-based fish treatments may cause temporary stress or hiding behavior, mild water discoloration, and reduced appetite during treatment.
If fish show severe distress such as rapid gill movement, loss of balance, or gasping at the surface, stop treatment and seek aquatic veterinary advice.
Birds
When doxycycline is given in food or drinking water, potential reactions can include decreased appetite, lethargy, or changes in droppings if the amount is too high or the bird is sensitive.
If your bird appears fluffed up, inactive, or stops eating, discontinue use and contact an avian veterinarian.
Invertebrates
Do not use Fix Doxy in tanks that contain shrimp, snails, or other invertebrates, as strong treatments may harm them.
Treat fish in a separate hospital tank whenever possible.
Safe Use in Your System
Whenever possible, treat fish in a hospital or quarantine tank, remove activated carbon and UV sterilizers, and follow label directions for dose and duration.
Do not mix Fix Doxy with other treatments unless advised by a veterinarian.
Important Safety Warning
Fix Doxy is intended for ornamental aquarium fish and non-food pet birds only. It is not for animals raised for food.
Store the product in a cool, dry place away from children and pets. Always follow label directions.
Shipping & Returns
Shipping Policy
Orders ship from our U.S. warehouse within one business day via USPS or UPS, with rates and delivery times calculated at checkout.
For full shipping details, please review our shipping policy.
Review Shipping Policy →Refund Policy
If there is an issue with your order, you may be able to return or exchange items within 30 days according to our store guidelines.
Before sending anything back, please review our refund policy carefully.
Review Refund Policy →Frequently Asked Questions
What is Fix Doxy used for?
Fix Doxy is used for certain bacterial problems affecting ornamental aquarium fish and non-food pet birds. These may include fin and tail rot, columnaris, gill disease, bacterial septicemia, internal bacterial infections, and certain avian respiratory infections.
What is in Fix Doxy (Fish Doxy)?
Each Fix Doxy tablet provides doxycycline hyclate at a strength of 100 mg per tablet.
What is the difference between Fish Doxy and Fix Doxy?
Fix Doxy provides the same doxycycline hyclate strength of 100 mg per tablet. The primary differences are the manufacturer, packaging, branding, and labeling. Fix Doxy is made by Aqua Soma Labs, while the former Fish Doxy line was associated with Thomas Labs.
Is Fix Doxy a replacement for Bird Biotic?
Fix Doxy is presented as the online replacement for the discontinued Bird Biotic product. It provides doxycycline hyclate in a 100 mg tablet form for ornamental fish and non-food pet birds.
Is Bird Biotic still available, and is Fix Doxy a true replacement?
The older Thomas Labs Bird Biotic line was discontinued. Fix Doxy is offered as a replacement with the same doxycycline strength in an updated Aqua Soma Labs product.
Is Fix Doxy the same as Aqua Doxy?
Fix Doxy is intended to replace older Aqua Doxy products and provides doxycycline hyclate in the same 100 mg tablet format. Always check the current product label before use.
Can I use Fix Doxy for dogs, cats, or chickens?
No. This product is labeled for ornamental aquarium fish and non-food pet birds. It is not intended for dogs, cats, humans, or animals raised for food.
Where can I buy doxycycline for fish online?
Fix Doxy doxycycline 100 mg tablets can be ordered through this online store and shipped from our U.S. warehouse according to the current shipping policy.
Is Fix Doxy available in 500 mg?
This Fix Doxy product contains 100 mg of doxycycline hyclate per tablet and is offered in 30-count and 60-count bottles.
How do I know if my fish or bird might need a treatment like Fix Doxy?
Possible signs in fish include frayed fins, cloudy or red body patches, sores, abnormal gill movement, appetite loss, hiding, or symptoms associated with columnaris.
Possible signs in birds include sneezing, wheezing, nasal discharge, fluffed feathers, lethargy, eye irritation, appetite loss, or changes in droppings. Similar symptoms may have different causes, so professional diagnosis is recommended when available.
How long should I treat with Fix Doxy 100 mg?
Follow the current bottle label. Treatment may generally continue for approximately 5 to 10 days unless a veterinarian advises otherwise. The supplied information states that treatment should be stopped and professional guidance requested if no improvement is seen after five days.
What size aquarium can one Fix Doxy tablet treat?
The supplied label guidance uses one 100 mg tablet for every 15 gallons, or approximately 57 litres, of treatment water.
Does Fix Doxy work in saltwater aquariums?
Fix Doxy is presented for use with ornamental fish in freshwater and saltwater treatment systems. A separate hospital tank is recommended whenever possible.
Can I use Fix Doxy in my main display or community tank?
A separate hospital or quarantine tank is preferred. This helps protect the main biological filter, prevents exposure of sensitive invertebrates, and makes it easier to monitor the treated fish and water quality.
Will Fix Doxy harm my aquarium's biofilter?
Antibacterial treatments may affect beneficial filter bacteria. Monitor ammonia and nitrite during treatment and use a separate treatment tank whenever possible.
Can Fix Doxy be used for pigeons and other pet birds?
Fix Doxy is presented for non-food pet birds, including racing pigeons. The correct amount depends on the bird, its weight, and the method of administration. Follow the label or the instructions of an avian veterinarian.
Can I combine Fix Doxy with other fish treatments?
Do not mix Fix Doxy with other treatments unless a qualified veterinarian specifically recommends the combination.
What should I do if my fish or bird is not improving on Fix Doxy?
Stop treatment and contact an aquatic or avian veterinarian if symptoms worsen or no improvement is seen within the period stated on the product label.
How should I store Fix Doxy tablets?
Store the bottle tightly closed in a cool, dry location away from direct sunlight, excessive heat, moisture, children, and pets. Follow all storage information printed on the current bottle.
How should I dispose of water or filter media that contained Fix Doxy?
Follow the product label and applicable local disposal requirements. Avoid releasing concentrated medication into drains, natural waterways, or outdoor water systems. Contact your local waste or water authority when disposal instructions are unclear.
More Fish & Bird Treatments
Fix Mox (Amoxicillin) 250/500 mg
A treatment for fin rot, dropsy, ulcers, and other bacterial infections in ornamental fish. Available in 30-count and 100-count capsules.
Shop Fix Mox →Fix Zole (Metronidazole) 250/500 mg
Targets anaerobic bacteria and protozoa including Hexamita and hole-in-the-head disease in ornamental fish. Available in 60-count bottles.
Shop Fix Zole →Fix Zithro (Azithromycin) 250 mg
A treatment for fin rot, columnaris, gill disease, and avian respiratory concerns. Available in 12-count and 30-count tablets.
Shop Fix Zithro →Fix Cin (Clindamycin) 150 mg
A treatment for Gram-positive bacterial infections, including skin and soft-tissue concerns in ornamental fish.
Shop Fix Cin →Fix Sulfa (SMZ/TMP) 960 mg
A treatment for a range of bacterial infections in ornamental fish.
Shop Fix Sulfa →Fix Pen (Penicillin) 500 mg
A treatment for Gram-positive bacterial infections in ornamental fish and non-food pet birds.
Shop Fix Pen →Fix Flex (Cephalexin) 250/500 mg
A treatment for fin rot, ulcers, and bacterial skin infections in ornamental fish.
Shop Fix Flex →Fix Flox (Ciprofloxacin) 500 mg
A treatment for Gram-negative bacterial infections, including fin rot, ulcers, columnaris, and septicemia in ornamental fish.
Shop Fix Flox →Browse All Treatments
Explore our complete Fish & Bird Treatments Collection for more Fix line products and related treatments.
Explore the Collection →Guides and Treatment Tips
Visit the Fish & Bird Treatments Blog for practical care guides, water-care advice, and treatment tips.
Visit the Blog →Transparency & Verification
How Product Information Is Verified
Who is responsible for this page: The store editorial team responsible for reviewing and maintaining product information.
Verification snapshot: This page is written from the current product label for this item and reviewed for accuracy and consistency before publishing.
How We Verify Product Information
Label-First Accuracy
Directions, duration, storage, and warnings are taken from the current product label for this item.
Specification Validation
Key details such as ingredient names and strengths, where applicable, are cross-checked against the manufacturer’s product specifications to reduce the risk of labeling mistakes.
Consistency Checks
We review for internal consistency, including matching directions and storage language across sections, and remove wording that could overpromise results.
Updates
We update pages when label directions, packaging, or manufacturer information changes.
See something that does not match the product you received? Please contact us so we can review and update the page.
Fish Azithromycin 250mg | Aquarium Fish Antibiotic
Regular price $39.99 Save $-39.99Fish Azithromycin 250mg | Aquarium Fish Antibiotic
Fish Zithro (Fix Zithro) supplies 250 mg of azithromycin per tablet and is an antibacterial treatment for ornamental aquarium fish and non-food pet birds.
It is often selected to help manage suspected bacterial problems such as fin and tail rot, columnaris, gill disease, and early respiratory signs in pet birds.
Often called Bird Zithro or Fish Zithro in the hobby community, Fix Zithro is a replacement for the discontinued Thomas Labs Bird Zithro, Fish Zithro, and Aqua Zithro 250 mg products.
This azithromycin tablet from the Aqua Soma Labs Fix range is used for common problems such as fin and tail rot, columnaris, gill disease, bacterial hemorrhagic septicemia, and other bacterial infections in freshwater and saltwater aquariums.
Bird keepers may also use it under veterinary guidance for mild upper respiratory tract infections, suspected Mycoplasma concerns, or conditions associated with Chlamydia psittaci, including psittacosis, parrot fever, and ornithosis in pigeons and other pet birds.
Azithromycin helps slow or stop the growth of certain bacteria affecting the gills, skin, and respiratory tract.
When used as directed, it works best alongside appropriate husbandry, clean water, stable environmental conditions, and suitable nutrition.
Fix Zithro from Aqua Soma Labs is available in bottles of 12 or 30 tablets with fresh expiration dates.
The two bottle sizes provide flexible options for hobbyists maintaining a single hospital tank, several community aquariums, or an aviary under veterinary guidance.
Use Fix Zithro when early signs of bacterial stress appear. Symptoms may differ between fish and birds, so the lists below separate the most common signs by species.
Fish-Specific Symptoms
- Clamped or frayed fins associated with fin and tail rot
- Red or cloudy patches on the body
- Fuzzy patches that may suggest columnaris
- Pop-eye or exophthalmia
- Gill irritation or labored gill movement
- Secondary bacterial problems around gill-fluke damage
- Listlessness or persistent appetite loss
Bird-Specific Symptoms
- Sneezing or nasal discharge
- Upper respiratory tract infection signs
- Swollen eyes or sinus irritation
- Suspected Mycoplasma-related concerns
- Signs associated with Chlamydia psittaci or parrot fever
- Ruffled feathers or a fluffed-up posture
- Reduced activity or appetite loss
Address suspected bacterial problems early, maintain clean water, and consult an aquatic or avian professional whenever one is available.
Combining treatment with proper husbandry gives fish and birds a better opportunity to recover while helping keep the aquarium or aviary stable.
Order online for same-day dispatch on qualifying orders placed before 1:30 p.m. CT, Monday through Friday. Fix Zithro ships directly from our United States warehouse through USPS or UPS.
Bird Zithro vs Fix Zithro: What Changed?
If you previously purchased Thomas Labs Bird Zithro, Fish Zithro, or Aqua Zithro, here is what has changed and what remains the same.
Same Azithromycin, Same Strength
Fix Zithro contains the same 250 mg of azithromycin per tablet associated with Bird Zithro, Fish Zithro, and Aqua Zithro.
New Manufacturer
Fix Zithro is made by Aqua Soma Labs in the United States, replacing the discontinued Thomas Labs product line.
Same Crushable Tablet Form
Fix Zithro uses a crushable tablet format that can be dissolved in aquarium water or administered to birds exactly as directed by an avian veterinarian.
12-Count and 30-Count Options
Choose a 12-count bottle for smaller setups or occasional use, or a 30-count bottle for multiple tanks or veterinarian-directed aviary management.
Benefits of Fix Zithro for Fish & Birds
Bacterial Support for Fish & Birds
Fix Zithro provides azithromycin for ornamental fish and non-food pet birds. It may help manage fin and tail rot, columnaris, gill disease, and early respiratory or ornithosis-complex signs when used as directed.
Ready to Use Promptly
Keeping Fix Zithro properly stored means treatment is available when early bacterial signs appear. Avian use should still follow professional veterinary guidance.
Helps With Internal and External Problems
Azithromycin may be used for skin lesions, ulcers, fin damage, and internal bacterial concerns in a hospital tank, as well as part of a veterinarian-directed plan for respiratory or Mycoplasma-related concerns in birds.
Consistent 250 mg Tablets
Each tablet contains a consistent 250 mg amount, simplifying treatment calculations across different aquarium volumes.
Easy to Prepare
Crushable tablets can be dissolved in aquarium water or administered to birds in the exact form and amount directed by an avian veterinarian.
Freshwater, Saltwater & Aviary Setups
Fix Zithro can be used in properly prepared freshwater or marine treatment systems and may be considered for pigeons and ornamental birds under veterinary supervision.
Ideal for Hospital Tanks and Quarantine
A separate hospital tank or treatment enclosure reduces unnecessary exposure of healthy animals and allows more accurate observation and treatment control.
Usage Guidelines & Instructions
Set Up a Separate Treatment Area
Move affected fish to a dedicated hospital or quarantine tank.
Where practical, birds requiring treatment should be separated into an appropriate treatment enclosure under veterinary guidance.
Separation helps protect healthy tank mates or flock members and allows more accurate observation and treatment.
Directions for Fish Aquariums
Dissolve one 250 mg tablet per 10 gallons or 38 litres of water in the hospital tank.
Mix the tablet in a clean cup of aquarium water first, then distribute the prepared solution evenly around the treatment tank.
Repeat the treatment every 24 hours for 5 to 7 days while closely monitoring water quality and fish behavior.
Follow the current bottle label or an aquatic veterinarian's instructions when they differ from this quick-reference information.
Use in Pet Birds Under Veterinary Guidance
Administer Fix Zithro to pigeons and other non-food pet birds only under the direction of an avian veterinarian.
The veterinarian should determine the correct amount for the bird's species, weight, condition, frequency, and treatment duration.
Tablets may be given whole, divided, or crushed and mixed with food or drinking water only as specifically instructed.
Maintain Water Quality & Finish Treatment
Perform partial water changes when needed between treatments to keep ammonia and nitrite low.
Maintain strong aeration throughout treatment.
Continue for the complete recommended duration, even if the animal appears better, unless a veterinarian advises otherwise.
If no improvement appears after several days, or symptoms worsen, consult an aquatic or avian professional.
Fix Zithro Amounts by Aquarium Size
| Tank volume | Azithromycin per use | 250 mg tablets |
|---|---|---|
| 10 gallons (38 L) | 250 mg | 1 tablet |
| 20 gallons (76 L) | 500 mg | 2 tablets |
| 30 gallons (114 L) | 750 mg | 3 tablets |
| 40 gallons (151 L) | 1,000 mg | 4 tablets |
| 55 gallons (208 L) | Approximately 1,375 mg | 5 to 6 tablets |
Amounts for Pet Birds
Bird amounts are determined by body weight rather than aquarium-water volume, so there is no universal bird chart.
The appropriate amount depends on the species, body weight, condition being treated, administration method, and overall health of the bird.
An avian veterinarian must determine the amount, frequency, and duration.
Do not estimate an avian amount independently or use the aquarium chart for birds.
What to Expect During Treatment
Days 1 to 2
Fish may hide or eat less, and treatment water may look slightly cloudy. Maintain the treatment schedule and keep aeration strong.
Days 3 to 5
Look for fin damage or red patches that stop spreading, returning appetite, and steadier breathing. Seek professional guidance if the fish worsen or no improvement appears by day five.
Days 5 to 7
Complete the recommended treatment even when improvement appears. Afterward, perform a partial water change and restore activated carbon.
What You Need for Treatment
Prepare the following supplies before starting treatment:
- A separate hospital or quarantine tank
- A heater suitable for the fish species
- An air stone or established sponge filter
- An ammonia and nitrite test kit
- A suitable aquarium dechlorinator
- A small net for careful transfer
- A clean cup for dissolving each tablet
Pro Tip: Quarantine affected fish and birds away from healthy companions whenever practical. A dedicated treatment setup makes observation, water changes, and treatment control easier while reducing unnecessary exposure.
How Fix Zithro Works
Azithromycin is the active ingredient in Fix Zithro, supplied at 250 mg per tablet.
In practical terms, azithromycin helps slow or stop the growth of certain susceptible bacteria affecting the gills, skin, and respiratory tract of ornamental fish and non-food pet birds.
The remainder of each tablet consists of standard inactive ingredients that help hold the tablet together, maintain stability during storage, and allow the tablet to disperse when mixed with aquarium water.
Bird administration should follow the exact preparation and delivery method supplied by an avian veterinarian.
Safety and Tank Notes
When used as directed, Fix Zithro generally causes no problems in ornamental fish and non-food pet birds.
Incorrect amounts, unnecessarily prolonged use, or repeated antibacterial treatment can increase the risk of side effects and antibacterial resistance.
Fish
Azithromycin-based aquarium treatment may cause temporary hiding, mild water cloudiness, reduced activity, or decreased appetite.
If severe distress appears, including rapid gill movement, loss of balance, surface gasping, or remaining on the bottom, stop treatment, improve aeration, perform an appropriate water change, and seek aquatic veterinary advice.
Birds
Possible reactions may include reduced appetite, loose or changed droppings, and lethargy, particularly when the amount is too high or the bird is sensitive.
If a bird becomes fluffed up, inactive, has difficulty breathing, or stops eating, discontinue treatment and contact an avian veterinarian.
Invertebrates
Do not use Fix Zithro in display aquariums containing shrimp, snails, corals, or other sensitive invertebrates whenever a separate treatment tank is available.
Strong antibacterial treatments may harm sensitive species or disrupt the aquarium ecosystem.
Safe Use in Your System
Treat fish in a hospital or quarantine tank whenever possible.
Remove activated carbon and switch off UV sterilization during treatment. Monitor ammonia, nitrite, oxygen, and temperature closely.
Do not combine Fix Zithro with other antibacterial products unless specifically advised by a veterinarian.
Important Safety Warning
Fix Zithro is intended for ornamental aquarium fish and non-food pet birds only. It is not intended for animals raised for food.
Store tablets in their original container in a cool, dry location protected from direct sunlight, excessive heat, and moisture.
Keep the container tightly closed and out of reach of children and animals.
Always follow the directions printed on the current product label.
Shipping & Returns
Shipping Policy
Orders ship from our United States warehouse within one business day through USPS or UPS.
Same-day dispatch may be available for qualifying orders placed before 1:30 p.m. CT, Monday through Friday.
Shipping rates and estimated delivery times are calculated at checkout.
Review Shipping Policy →Refund Policy
If there is an issue with your order, eligible items may be returned or exchanged within 30 days according to the current store guidelines.
Review the full refund policy before returning any item.
Review Refund Policy →Frequently Asked Questions
What is Fix Zithro used for in fish and birds?
Fix Zithro contains azithromycin and is used for certain bacterial concerns in ornamental aquarium fish. These may include fin and tail rot, columnaris, gill disease, red or cloudy body areas, and certain internal bacterial problems.
In non-food pet birds, it may form part of a veterinarian-directed plan for certain respiratory, Mycoplasma-related, or Chlamydia psittaci concerns.
What is the difference between Bird Zithro and Fix Zithro?
Fix Zithro is the current Aqua Soma Labs product replacing discontinued Thomas Labs Bird Zithro and Fish Zithro products. It provides the familiar 250 mg azithromycin tablet strength in updated packaging.
Is Fix Zithro a replacement for Aqua Zithro?
Fix Zithro is presented as the current Aqua Soma Labs replacement for older Aqua Zithro products and provides 250 mg of azithromycin per tablet.
Is Fix Zithro the same as Fish Zithro?
Fix Zithro is intended as the updated replacement for discontinued Fish Zithro products, with the same 250 mg azithromycin tablet strength and updated branding.
Where can I buy azithromycin for fish online?
Fix Zithro 250 mg tablets can be ordered through this online store in 12-count or 30-count bottles and shipped according to the current store shipping policy.
Is azithromycin stronger than amoxicillin for fish?
Azithromycin and amoxicillin are different antibacterial ingredients with different activity profiles. One is not automatically better or stronger for every infection. The appropriate choice depends on the suspected organism and the condition being treated.
How do I know if my fish might need azithromycin?
Possible bacterial signs include frayed fins, fuzzy or red body patches, cloudy areas, gill irritation, pop-eye, appetite loss, and reduced activity.
Similar signs may also be caused by parasites, fungal conditions, injuries, or poor water quality, so professional assessment is recommended when the cause is unclear.
Is azithromycin for birds the same as fish azithromycin?
Fix Zithro contains azithromycin, but bird administration is based on body weight, species, condition, and veterinary instructions. Aquarium calculations must not be used for birds.
What size aquarium can one Fix Zithro tablet treat?
The supplied aquarium guideline uses one 250 mg tablet per 10 gallons or approximately 38 litres of treatment water.
Is fish azithromycin available in 500 mg?
This Fix Zithro product is supplied in a 250 mg tablet strength. A 500 mg treatment amount would require two 250 mg tablets according to the supplied aquarium chart.
How long should I treat with Fix Zithro?
The supplied directions describe one treatment every 24 hours for approximately 5 to 7 days. Always follow the current bottle label or veterinary instructions.
How soon should I see improvement?
Improvement may appear within three to five days through steadier breathing, returning appetite, improved activity, and bacterial lesions that stop spreading.
Seek professional advice if the animal becomes worse or no improvement appears after several days.
What should I do after finishing treatment?
Follow the product label, perform an appropriate partial water change, and restore activated carbon if normally used. Continue monitoring water quality and the condition of the treated fish.
Can I use Fix Zithro in my main community or reef tank?
A separate hospital tank is preferred. This reduces unnecessary exposure of healthy fish and sensitive invertebrates and helps protect the display aquarium's biological filtration.
Does Fix Zithro work in saltwater aquariums?
Fix Zithro is presented for use in properly prepared freshwater and saltwater treatment tanks. A separate hospital tank is especially important for marine systems containing corals or invertebrates.
Can Fix Zithro be used for racing pigeons?
Fix Zithro may be considered for non-food pet birds, including racing pigeons, only under the direction of an avian veterinarian who determines the correct amount and duration.
Can I combine Fix Zithro with other fish treatments?
Do not combine Fix Zithro with other antibacterial or aquarium treatments unless a qualified veterinarian specifically recommends the combination.
Can Fix Zithro treat fungal, viral, or parasitic infections?
Fix Zithro is an antibacterial product. It should not be expected to treat fungal, viral, or parasitic conditions unless a professional has identified a separate appropriate reason for its use.
Is Fix Zithro safe for betta fish and small aquariums?
Small aquariums require careful volume calculations. The supplied guide is one 250 mg tablet per 10 gallons, so a smaller tank may require an accurately divided amount. Follow the bottle label or consult an aquatic veterinarian rather than estimating.
How should I store and dispose of Fix Zithro tablets?
Store tablets tightly closed in a cool, dry place protected from direct sunlight and moisture.
Follow the current label and applicable local requirements when disposing of unused tablets, treatment water, or filter media. Avoid releasing concentrated treatment into natural waterways.
More Fish & Bird Treatments
Fix Mox (Amoxicillin) 250/500 mg
A treatment for fin rot, dropsy, ulcers, and other bacterial concerns in ornamental fish. Available in 30-count and 100-count capsules.
Shop Fix Mox →Fix Zole (Metronidazole) 250/500 mg
Targets certain anaerobic organisms and protozoa associated with Hexamita and hole-in-the-head concerns. Available in 60-count bottles.
Shop Fix Zole →Fix Doxy (Doxycycline) 100 mg
A treatment for columnaris, respiratory concerns, and Mycoplasma-related problems in ornamental fish and non-food pet birds.
Shop Fix Doxy →Fix Cin (Clindamycin) 150 mg
A treatment for certain Gram-positive bacterial concerns, including skin and soft-tissue problems in ornamental fish.
Shop Fix Cin →Fix Sulfa (SMZ/TMP) 960 mg
A treatment used for a range of bacterial concerns affecting ornamental aquarium fish.
Shop Fix Sulfa →Fix Pen (Penicillin) 500 mg
A treatment for certain Gram-positive bacterial concerns in ornamental fish and non-food pet birds.
Shop Fix Pen →Fix Flex (Cephalexin) 250/500 mg
A treatment for fin rot, ulcers, and certain bacterial skin concerns in ornamental fish and non-food pet birds.
Shop Fix Flex →Fix Flox (Ciprofloxacin) 500 mg
A treatment for certain Gram-negative bacterial concerns including fin rot, ulcers, columnaris, and septicemia.
Shop Fix Flox →Browse All Treatments
Explore our complete Fish & Bird Antibacterial Collection for additional Fix line products and related treatments.
Explore the Collection →Guides and Treatment Tips
Visit the Fish & Bird Antibacterial Care Blog for practical care guides, aquarium water advice, and treatment information.
Visit the Blog →Transparency & Verification
How Product Information Is Verified
Who is responsible for this page: The store editorial team responsible for reviewing and maintaining product information.
Verification snapshot: This page is written from the current product label for this item and reviewed for accuracy and consistency before publishing.
How We Verify Product Information
Label-First Accuracy
Directions, duration, storage information, and warnings are taken from the current product label for this item.
Specification Validation
Key details such as the active ingredient, tablet strength, and bottle counts are cross-checked against available manufacturer specifications.
Consistency Checks
Product content is reviewed for consistent strengths, directions, safety information, and storage details throughout the page.
Updates
Pages are updated when the product label, packaging, tablet count, manufacturer information, or directions change.
See something that does not match the product you received? Please contact us so the information can be reviewed and updated.
Fish Mox Amoxicillin 250mg & 500mg | Fish Antibiotic
Regular price $24.99 Save $-24.99Fish Mox Amoxicillin 250mg & 500mg | Fish Antibiotic
Fish Mox (Fix Mox) is a fish amoxicillin treatment in 250 mg and 500 mg capsules for ornamental aquarium fish and non-food pet birds.
In freshwater and saltwater tanks it is used for common bacterial problems including dropsy or body swelling, fin and tail rot, columnaris, hemorrhagic septicemia, red streaks, gill disease, swim bladder infections, abscesses, and skin ulcers.
With an avian veterinarian's guidance, the same capsules can be part of an amoxicillin plan for problems such as crop infections and salmonella or paratyphoid in pigeons and other pet birds.
Fix Mox gives you a 250 mg or 500 mg strength, so you can match it to the job: a small hospital tank, a larger community aquarium, or, with veterinary input, a loft or aviary.
It is the current replacement for the discontinued Thomas Labs Fish Mox, also known as fishmox. The 250 mg option stands in for the original strength, and the 500 mg option covers what aquarists knew as Fish Mox Forte and Aqua Mox.
Stock ships from our United States warehouse with fresh expiration dates and clearly printed strengths.
Start treatment early, at the first signs of bacterial stress. Those signs differ between fish and birds, so use the lists below to know what to watch for.
Fish-Specific Symptoms
- Fin and tail rot, including frayed or rotting fins
- Dropsy or body swelling
- Pop-eye or bulging eyes
- Red streaks or open sores on the body
- Skin ulcers and abscesses
- Columnaris and gill disease
- Lethargy, rapid breathing, or appetite loss
Bird-Specific Symptoms Under Veterinary Guidance
- Crop infections
- Suspected salmonella or paratyphoid
- Fluffed-up feathers, lethargy, or inactivity
- Decreased appetite
- Loose or changed droppings
- Labored or difficult breathing
For birds, only use Fix Mox when an avian veterinarian has recommended amoxicillin for a specific problem. Catching an infection early, paired with clean water and good housing, gives your fish and birds the best chance to recover.
Order online and enjoy same-day dispatch on orders placed before 1:30 p.m. CT, Monday through Friday. Fix Mox ships directly from our United States warehouse via USPS or UPS.
Fish Mox vs Fix Mox: What Changed?
If you used to buy Fish Mox, Fish Mox Forte, or Aqua Mox, those brands are now discontinued or hard to find. Fix Mox from Aqua Soma Labs uses the same amoxicillin at the same strengths and steps in as a direct replacement for aquarium use.
Same Amoxicillin Inside
Fish Mox and Fix Mox both contain amoxicillin at 250 mg or 500 mg per capsule, the strengths aquarists have relied on for years.
Updated Labeling & Packaging
Fix Mox carries clear, modern labeling, with usage guidance, amoxicillin strength, and storage notes printed on the bottle.
Same Capsule Form
Pull-apart capsules dissolve in tank water, matching the format aquarists knew from Thomas Labs Fish Mox or Aqua Mox.
Fresh Stock & Current Expiration Dates
Every bottle ships with recent production and clearly printed expiration dates.
Benefits of Fix Mox for Fish & Birds
Covers Common Fish Infections
As an aquarium antibacterial treatment, amoxicillin is used against many of the bacteria behind dropsy, fin and tail rot, red streaks, gill disease, swim bladder infections, and skin ulcers in freshwater and saltwater tanks.
Handles External and Internal Problems
Use it for outward signs such as frayed fins, open sores, or red patches, and for internal infections such as hemorrhagic septicemia that bring swelling, lethargy, or appetite loss. Treat affected fish in a hospital tank.
Flexible 250 mg and 500 mg Strengths
Amoxicillin in a 500 mg or 250 mg capsule lets you scale from a small quarantine tank to a larger system. A common guide is 250 mg per 10 gallons or 500 mg per 20 gallons.
Keep a Bottle on Hand
Bacterial problems move quickly, so keeping Fix Mox stored properly means it is available at the first sign of a bacterial problem in your aquarium.
Easy to Prepare for Fish and Vet-Directed Birds
The capsules pull apart, and the contents dissolve in tank water. Under avian veterinary guidance, the contents may be mixed into soft food or water for birds with specific bacterial problems.
Built for Hospital and Quarantine Tanks
A separate treatment tank lets you remove carbon and UV, maintain stable water quality, and watch sick fish without treating healthy tank mates or sensitive invertebrates.
A Modern Swap for Discontinued Brands
When older Thomas Labs Fish Mox or Aqua Mox products are unavailable, Fix Mox provides a modern replacement with clear strength labels and fresh stock.
Usage Guidelines & Instructions
Set Up a Separate Treatment Area
Move sick fish to a dedicated hospital or quarantine tank before you dose. Take out activated carbon and switch off UV sterilizers, since both can remove amoxicillin from the water.
A 20% to 25% water change before the first dose lowers stress and starts treatment with cleaner water.
Directions for Fish Aquariums
Follow the label guide of 250 mg amoxicillin per 10 gallons or 38 litres, or 500 mg per 20 gallons or 76 litres.
Open the capsule, stir the powder into a cup of tank water, then pour it evenly around the treatment tank.
Repeat every 24 hours for 5 to 10 days, with a partial water change between doses. If nothing improves after about five days, or fish look worse, stop and ask an aquatic veterinarian.
Use in Pet Birds Under Veterinary Guidance
Use Fix Mox in pigeons and other non-food pet birds only when an avian veterinarian directs it.
The veterinarian sets the correct amount for the bird's weight, how often to give it, and how long to continue.
Capsules may be opened into soft food or drinking water so the bird receives the full intended amount, but follow the veterinarian's exact instructions rather than estimating.
Maintain Water Quality and Finish the Treatment
During treatment, monitor ammonia, nitrite, temperature, and aeration.
Finish the full treatment unless a veterinarian says otherwise. Stopping too early may allow symptoms to return.
Afterward, perform a partial water change and restore activated carbon to help remove remaining amoxicillin.
Fix Mox Amounts by Aquarium Size
| Tank volume | Amoxicillin per use | 250 mg capsules | 500 mg capsules |
|---|---|---|---|
| 10 gallons (38 L) | 250 mg | 1 capsule | Not applicable |
| 20 gallons (76 L) | 500 mg | 2 capsules | 1 capsule |
| 30 gallons (114 L) | 750 mg | 3 capsules | 1 capsule plus one 250 mg capsule |
| 40 gallons (151 L) | 1,000 mg | 4 capsules | 2 capsules |
| 55 gallons (208 L) | Approximately 1,375 mg | 5 to 6 capsules | Approximately 3 capsules |
What to Expect During Treatment
Days 1 to 2
Fish may hide or eat less, and the water may appear slightly cloudy. Keep dosing on schedule and maintain strong aeration.
Days 3 to 5
Look for sores or red patches that stop spreading, returning appetite, and steadier breathing. If there is no change by day five, or fish look worse, seek aquatic veterinary advice.
Days 5 to 10
Even when fish improve, complete the recommended treatment. After treatment, perform a partial water change and restore activated carbon.
What You Need for Treatment
A little preparation before the first dose saves trouble later.
- A separate hospital or quarantine tank so the full display aquarium is not treated
- A heater and air stone or sponge filter for stable temperature and strong aeration
- An ammonia and nitrite test kit for monitoring water quality
- A dechlorinator for water changes between doses
- A small net and clean cup for transferring fish and preparing each dose
Pro Tip: Treat sick fish in a separate hospital tank rather than the main display whenever possible. This protects the main biological filter and sensitive invertebrates while concentrating the treatment where it is needed.
How Fix Mox Works
Each Fix Mox capsule contains amoxicillin trihydrate at a strength of 250 mg or 500 mg.
Amoxicillin is an antibacterial used against many Gram-positive and some Gram-negative bacteria, including bacteria associated with fin and tail rot, skin ulcers, red streaks, and certain gill infections in ornamental fish.
Alongside the amoxicillin, each capsule contains standard ingredients that hold the capsule contents together and help them disperse properly in aquarium water or, for birds under veterinary guidance, in soft food.
Safety and Tank Notes
When used at the correct amount, Fix Mox usually causes no problems for ornamental fish or pet birds. The risk of side effects increases with excessive amounts, unnecessarily prolonged treatment, or use in an already severely stressed animal.
Unnecessary or repeated use can also contribute to antibacterial resistance.
Fish
Amoxicillin may cause temporary hiding, mild water cloudiness, or reduced appetite during treatment.
If a fish shows rapid gill movement, loss of balance, surface gasping, or remains on the bottom, stop treatment, improve aeration, add clean dechlorinated water, and contact an aquatic veterinarian.
Birds
When mixed into food or drinking water, amoxicillin may cause reduced appetite, loose or changed droppings, or lethargy, especially if the amount is too high or the bird is sensitive.
A fluffed-up or inactive bird, or one that has difficulty breathing or stops eating, should stop treatment and receive avian veterinary attention.
Invertebrates
Do not use Fix Mox in display tanks containing shrimp, snails, or other sensitive invertebrates.
Move affected fish to a separate hospital or quarantine tank whenever possible.
Safe Use in Your System
Remove activated carbon and switch off UV sterilization during treatment. Monitor ammonia, nitrite, temperature, and oxygen levels.
Do not combine Fix Mox with other treatments unless a veterinarian specifically advises it.
Important Safety & Storage Information
Fix Mox is for aquarium and ornamental fish and non-food pet birds only. It is not for animals raised for food.
If you are sensitive to penicillins, avoid direct contact with the capsule contents. Wash your hands after handling and wear suitable gloves when needed.
Store the capsules in their original container in a cool, dry location at 59–86°F or 15–30°C. Protect them from moisture and direct sunlight, keep the lid closed, and store out of reach of children and animals.
Shipping & Returns
Shipping Policy
Orders ship from our United States warehouse within one business day through USPS or UPS. Rates and estimated delivery times are calculated at checkout.
For complete shipping details, review our shipping policy.
Review Shipping Policy →Refund Policy
If there is an issue with your order, eligible products may be returned or exchanged within 30 days according to our store guidelines.
Review the complete refund policy before sending a product back.
Review Refund Policy →Frequently Asked Questions
What is Fix Mox used for in fish and birds?
Fix Mox contains amoxicillin and is intended for certain bacterial problems in ornamental fish. These may include fin and tail rot, dropsy, red streaks, ulcers, abscesses, columnaris, septicemia, and certain gill infections.
For non-food pet birds, use should only occur under the guidance of an avian veterinarian.
Is Fix Mox the same as Fish Mox or Aqua Mox?
Fix Mox is presented as the current Aqua Soma Labs replacement for discontinued Fish Mox, Fish Mox Forte, and Aqua Mox products. It is available in the familiar 250 mg and 500 mg amoxicillin capsule strengths.
Is Fix Mox, also called fish mox, the same as amoxicillin?
The active ingredient in Fix Mox is amoxicillin trihydrate. Each capsule is clearly labeled as containing either 250 mg or 500 mg.
Is Fix Mox the same as fish amoxicillin 500 mg?
The 500 mg Fix Mox option contains 500 mg of amoxicillin per capsule. A separate 250 mg strength is also available.
Where can I buy Fish Mox amoxicillin online?
Fix Mox capsules can be ordered through this online store and shipped from our United States warehouse according to the current shipping terms.
Can Fix Mox be used for dogs or cats?
No. This product is labeled for ornamental aquarium fish and non-food pet birds. It is not intended for dogs, cats, humans, or food-producing animals.
What is the difference between Fish Mox and Fish Mox Forte?
The traditional Fish Mox product used the 250 mg strength, while Fish Mox Forte referred to the stronger 500 mg capsule. Fix Mox is available in both 250 mg and 500 mg strengths.
How do I know if my fish might need a fish amoxicillin treatment?
Possible bacterial signs include frayed or rotting fins, swelling, red streaks, sores, ulcers, bulging eyes, abnormal breathing, lethargy, or appetite loss.
Similar signs can also result from poor water quality, parasites, fungal problems, or other conditions, so professional assessment is recommended when the cause is uncertain.
Can I use Fix Mox in my main community or reef tank?
A separate hospital or quarantine tank is preferred. This reduces exposure of healthy tank mates and sensitive invertebrates and helps protect the main aquarium's biological filtration.
How much Fix Mox should I use per gallon?
The supplied label-style reference is 250 mg per 10 gallons, which is approximately 25 mg per gallon. Follow the current bottle label rather than relying only on a general calculation.
How long should I treat with Fix Mox?
The supplied instructions describe treatment every 24 hours for approximately 5 to 10 days, with partial water changes between doses. Always follow the current product label.
Does Fix Mox work in saltwater aquariums?
Fix Mox is presented for ornamental fish in freshwater and saltwater treatment systems. A separate hospital tank is recommended, especially for marine aquariums containing invertebrates.
Is Fix Mox safe for pet birds, and can I treat more than one bird?
Use in non-food pet birds should only occur under avian veterinary guidance. The correct amount depends on the species, body weight, condition, administration method, and number of birds being treated.
Will Fix Mox affect beneficial bacteria in my aquarium?
Antibacterial treatments may interfere with beneficial biological filtration. Use a separate treatment tank and monitor ammonia and nitrite closely.
Can Fix Mox treat fungal, viral, or parasitic infections?
Fix Mox contains an antibacterial ingredient. It should not be assumed to treat fungal, viral, or parasitic conditions unless a qualified professional has identified an appropriate reason for its use.
Can I combine Fix Mox with other treatments?
Do not combine Fix Mox with other aquarium or bird treatments unless a veterinarian specifically recommends the combination.
What is the active ingredient in Fish Mox?
The active ingredient is amoxicillin trihydrate, supplied as either 250 mg or 500 mg per capsule.
How should I store Fix Mox capsules?
Keep the capsules in their original, tightly closed container at 59–86°F or 15–30°C. Protect the bottle from moisture, excessive heat, and direct sunlight, and keep it away from children and animals.
What should I do if my fish are not improving on Fix Mox?
Stop treatment and seek aquatic veterinary advice if the fish become worse or show no improvement after the period specified on the product label.
What is fish mox?
Fish Mox is a commonly used name for amoxicillin capsules labeled for ornamental aquarium fish. Fix Mox is the current Aqua Soma Labs product offered in 250 mg and 500 mg capsule strengths.
More Fish & Bird Treatments
Fix Zole (Metronidazole) 250/500 mg
A treatment for Hexamita, hole-in-the-head disease, and other protozoa-related problems in ornamental fish. Available in 60-count bottles.
Shop Fix Zole →Fix Doxy (Doxycycline) 100 mg
A treatment for columnaris, respiratory infections, and Mycoplasma concerns in ornamental fish and non-food pet birds. Available in 30-count and 60-count tablets.
Shop Fix Doxy →Fix Zithro (Azithromycin) 250 mg
A treatment for fin rot, columnaris, gill disease, and avian respiratory concerns. Available in 12-count and 30-count tablets.
Shop Fix Zithro →Fix Cin (Clindamycin) 150 mg
A treatment for Gram-positive bacterial problems, including skin and soft-tissue concerns, in ornamental fish.
Shop Fix Cin →Fix Sulfa (SMZ/TMP) 960 mg
A treatment used against a range of bacterial infections in ornamental fish.
Shop Fix Sulfa →Fix Pen (Penicillin) 500 mg
A treatment for Gram-positive bacterial problems in ornamental fish and non-food pet birds.
Shop Fix Pen →Fix Flex (Cephalexin) 250/500 mg
A treatment for fin rot, ulcers, and bacterial skin infections in ornamental fish and non-food pet birds.
Shop Fix Flex →Fix Flox (Ciprofloxacin) 500 mg
A treatment for Gram-negative bacterial problems, including fin rot, ulcers, columnaris, and septicemia, in ornamental fish and non-food pet birds.
Shop Fix Flox →Browse All Treatments
Explore our complete Fish & Bird Antibacterials Collection for more Fix line products and related treatments.
Explore the Collection →Guides and Treatment Tips
Visit the Fish & Bird Treatments Blog for practical usage guides, water-care advice, and treatment tips.
Visit the Blog →Transparency & Verification
How Product Information Is Verified
Who is responsible for this page: The store editorial team responsible for reviewing and maintaining product information.
Verification snapshot: This page is written from the current product label for this item and reviewed for accuracy and consistency before publishing.
How We Verify Product Information
Label-First Accuracy
Directions, duration, storage, and warnings are taken from the current product label for this item.
Specification Validation
Key details such as ingredient names and strengths are cross-checked against manufacturer specifications to reduce the risk of labeling mistakes.
Consistency Checks
We review the page for internal consistency and remove wording that could overpromise results.
Updates
Pages are updated when label directions, packaging, strengths, or manufacturer information changes.
See something that does not match the product you received? Please contact us so we can review and update the page.
Fish Fluconazole 100mg (Fish Flucon) | Fish Antifungal
Regular price $51.99 Save $-51.99Fish Fluconazole 100mg (Fish Flucon) | Fish Antifungal
Fish Flucon (Fix Flucon) is a fluconazole-based antifungal treatment formulated for ornamental aquarium fish.
Each tablet contains 100 mg of fluconazole and is designed to dissolve in treatment water for aquarium fish showing signs consistent with a susceptible fungal problem.
Fix Flucon is commonly considered for topical fungal growths visible on the skin, fins, mouth area, or damaged tissue, as well as certain systemic fungal concerns affecting ornamental fish.
Aquarium keepers may recognize this type of product under older names such as Fish Flucon, Fish Fluconazole, Aqua Flucon, or aquarium fluconazole.
Fix Flucon is the current Aqua Soma Labs version supplied in a clearly labeled 100 mg tablet strength.
Fluconazole is an antifungal ingredient rather than an antibacterial. It is intended for susceptible fungal organisms and should not be expected to treat ordinary bacterial fin rot, columnaris, parasites, viral disease, or poor-water-quality problems.
Fungal growth often appears after an injury, stress event, poor water conditions, or another disease has damaged the fish's protective skin and slime coat.
Correcting water quality, reducing stress, maintaining suitable temperature, and identifying the underlying cause remain essential parts of treatment.
Begin by moving the affected fish to a separate hospital or quarantine tank whenever possible.
Visible External Signs
- White or gray cotton-like growth on the skin
- Fuzzy growth around damaged fins or wounds
- Fungal growth on an injured mouth area
- Pale or discolored patches that appear raised or wool-like
- Fungal growth around an ulcer or damaged scale
- Fin deterioration accompanied by visible fuzzy material
- Egg fungus in a separate breeding or treatment setup
Possible Systemic or Advanced Signs
- Persistent loss of appetite
- Progressive weight loss
- Reduced activity or unusual hiding
- Loss of normal coloration
- Abnormal or circular swimming
- Bulging eyes associated with a wider health problem
- Recurring lesions that do not improve after water correction
Use Fix Flucon alongside stable water conditions, strong aeration, suitable nutrition, and careful daily observation.
When the cause is uncertain, or the fish is deteriorating rapidly, consult an aquatic veterinarian or experienced fish-health professional.
Order online: In-stock orders ship from our United States warehouse according to the current store processing and shipping schedule.
Fish Flucon vs Fix Flucon: What Changed?
Aquarium keepers who previously purchased Fish Flucon, Fish Fluconazole, or similar aquarium fluconazole products can use the comparison below to understand the current Fix Flucon presentation.
Fluconazole 100 mg
Each Fix Flucon tablet provides 100 mg of fluconazole for aquarium antifungal use.
Aqua Soma Labs Fix Line
Fix Flucon is supplied under the Aqua Soma Labs Fix product line with updated branding and packaging.
Dissolvable Treatment Form
The tablet can be pre-dissolved in aquarium water before being distributed throughout a hospital tank.
10-Count Supply
The compact bottle is suited to a dedicated hospital tank, smaller aquarium setup, or short label-directed treatment plan.
Benefits of Fix Flucon for Aquarium Fish
Targeted Antifungal Ingredient
Fluconazole is formulated to target susceptible fungal organisms rather than bacteria, viruses, or parasites.
External and Systemic Fungal Support
Fix Flucon may be considered for visible fungal growth and certain deeper fungal concerns when the suspected organism is sensitive to fluconazole.
Consistent 100 mg Tablets
Each tablet supplies a fixed 100 mg amount, helping aquarium keepers calculate treatment according to the actual hospital-tank water volume.
Easy to Pre-Dissolve
Tablets can be mixed in a clean cup of aquarium water before being added evenly throughout the treatment system.
Useful for Hospital Tanks
A separate treatment tank allows closer observation while protecting healthy fish, sensitive invertebrates, and the display aquarium.
Freshwater and Marine Treatment Setups
Fix Flucon may be used in an appropriately prepared freshwater or saltwater hospital tank when consistent with the current label.
Clear Antifungal Purpose
The product provides an antifungal option for situations where visible growth or other signs suggest fungus rather than a bacterial or parasitic condition.
Usage Guidelines & Instructions
Quick Usage Summary
Pre-dissolve one 100 mg tablet for every 5 gallons or approximately 19 litres of treatment water.
Administer once every 24 hours for five consecutive days according to the current product directions.
Discontinue treatment and reassess the diagnosis if no improvement is noted after five days.
Confirm That the Problem Appears Fungal
Look for raised white, gray, or cotton-like growth attached to damaged skin, fins, wounds, or eggs.
Do not assume every white patch is fungus. Columnaris, excess mucus, parasites, and damaged tissue can appear similar.
Prepare a Separate Treatment Tank
Move affected fish to a hospital or quarantine tank whenever possible.
Maintain stable temperature, strong aeration, and suitable filtration without activated carbon.
Switch off ultraviolet sterilization during treatment unless the current product label directs otherwise.
Measure the Actual Water Volume
Calculate the amount of water actually being treated rather than relying only on the aquarium's advertised capacity.
Substrate, rocks, decorations, equipment, and the fill level reduce the real water volume.
Pre-Dissolve the Tablet
Place the required tablet amount in a clean cup containing aquarium water.
Mix thoroughly, then distribute the prepared solution evenly throughout the treatment tank.
Administer Once Every 24 Hours
Use one 100 mg tablet for every 5 gallons or approximately 19 litres of actual treatment water.
Repeat once daily according to the current label directions.
Continue for Five Consecutive Days
Continue treatment for five consecutive days while checking the fungal growth, appetite, activity, breathing, and water parameters.
Do not extend treatment beyond the current label directions without aquatic veterinary guidance.
Stop if There Is No Improvement
Discontinue use if no improvement is noted after five days.
Reassess the diagnosis because the condition may be bacterial, parasitic, viral, environmental, or resistant to the selected treatment.
Fix Flucon Amounts by Aquarium Size
| Tank volume | Fluconazole per use | 100 mg tablets |
|---|---|---|
| 5 gallons (19 L) | 100 mg | 1 tablet |
| 10 gallons (38 L) | 200 mg | 2 tablets |
| 20 gallons (76 L) | 400 mg | 4 tablets |
| 30 gallons (114 L) | 600 mg | 6 tablets |
| 40 gallons (151 L) | 800 mg | 8 tablets |
What to Expect During Treatment
Days 1 to 2
The visible growth may remain present while treatment begins. Fish may hide or eat less because of the illness or transfer to a hospital tank.
Days 3 to 4
Look for growth that stops spreading, appears reduced, or begins separating from damaged tissue. Appetite and activity may gradually improve.
Day 5
Complete the label-directed course and reassess. Stop treatment and seek professional guidance if there is no improvement or the fish become worse.
What You Need for Treatment
- A separate hospital or quarantine tank
- A suitable aquarium heater
- An air stone or established sponge filter
- An ammonia and nitrite test kit
- A suitable water conditioner or dechlorinator
- A small net for gentle fish transfer
- A clean cup for pre-dissolving the tablets
- Activated carbon for use after treatment, when appropriate
Pro Tip: Correct the underlying cause while treating the fungus. Check for sharp decorations, fighting, parasites, poor water quality, temperature stress, and injuries that may have damaged the fish's protective skin.
How Fix Flucon Works
Each Fix Flucon tablet contains 100 mg of fluconazole, a triazole antifungal ingredient.
Fluconazole interferes with the production of important sterol components used by susceptible fungal cell membranes.
Disrupting this process can limit fungal growth and give affected tissue an opportunity to recover when the organism is susceptible and the aquarium environment is stable.
Fix Flucon is intended for fungal concerns. It does not replace antibacterial treatments for bacterial infections and does not target parasites or viruses.
Treatment success depends on correct identification of the problem, appropriate water conditions, the health of the fish, and whether the organism is sensitive to fluconazole.
Standard inactive tablet ingredients help maintain tablet stability and allow the product to disperse after it is pre-dissolved in aquarium water.
Safety and Tank Notes
Use Fix Flucon only according to the current product label and monitor fish and water quality closely during treatment.
Incorrect amounts, prolonged treatment, unnecessary repeat courses, or combining products may increase stress and make it harder to identify the original cause.
Possible Fish Reactions
Sick fish may temporarily hide, eat less, or appear lethargic during treatment.
These signs may result from the underlying illness, transfer stress, water-quality changes, or treatment sensitivity.
Stop Treatment If
Stop treatment if fish develop severe weakness, rapid gill movement, surface gasping, loss of balance, rolling, or a rapid decline.
Increase aeration, perform an appropriate partial water change, and seek aquatic veterinary guidance.
Water Quality
Test ammonia and nitrite regularly and maintain stable temperature and oxygen levels.
Poor water quality can worsen fungal growth and prevent damaged tissue from recovering.
Filtration During Treatment
Remove activated carbon and other chemical filtration media during treatment because they may reduce the amount of product available in the water.
Switch off UV sterilization unless the current label directs otherwise.
Invertebrates and Reef Systems
Treat affected fish in a separate hospital tank rather than exposing shrimp, snails, corals, and other sensitive invertebrates.
Sensitivity may vary between species and aquarium systems.
Do Not Mix Treatments
Do not combine Fix Flucon with antibacterial, antiparasitic, or other antifungal treatments unless the product labels permit it or a qualified professional recommends the combination.
Important Warnings & Precautions
Aquarium use only: Fix Flucon is intended for ornamental aquarium fish.
Not for human use: Do not ingest the tablets or use them for human treatment.
Not for food fish: Do not use on fish or other animals intended for human consumption.
Storage: Keep the bottle tightly closed in a cool, dry location protected from direct sunlight, excessive heat, and moisture.
Keep out of reach of children and animals.
Always follow the directions and warnings printed on the bottle received with the order.
Shipping & Returns
Shipping Policy
Orders ship from our United States warehouse through the available USPS or UPS services.
Processing times, shipping prices, and estimated delivery dates are shown according to the current store policy and checkout options.
Review Shipping Policy →Refund Policy
If there is an issue with the order, eligible products may qualify for a return or exchange according to the current store guidelines.
Review the full refund policy before returning any product.
Review Refund Policy →Frequently Asked Questions
What is Fix Flucon used for?
Fix Flucon contains fluconazole and is intended for susceptible topical and systemic fungal problems affecting ornamental aquarium fish.
What is the active ingredient in Fix Flucon?
Each tablet contains 100 mg of fluconazole.
What is the difference between Fish Flucon and Fix Flucon?
Fish Flucon is a commonly used name for aquarium fluconazole products. Fix Flucon is the current Aqua Soma Labs product supplied in a 100 mg tablet strength.
How many tablets are in a bottle?
This Fix Flucon product is supplied in a 10-count bottle.
What kinds of fungal problems may Fix Flucon help manage?
Fix Flucon may be considered for susceptible topical or systemic fungal concerns, including Saprolegnia-type growth and certain Ichthyophonus-related problems.
How can I tell whether the white growth is fungal?
Fungal growth often appears raised, fuzzy, cotton-like, or wool-like and may develop on injured skin, fins, wounds, or eggs.
Bacterial columnaris, excess mucus, parasites, and damaged tissue can look similar, so diagnosis is important.
Can Fix Flucon treat cotton-mouth disease?
Not every cotton-like mouth lesion is fungal. Columnaris is a bacterial condition that may appear cotton-like and generally requires a different treatment approach.
Use Fix Flucon only when the problem is reasonably suspected to be fungal.
Can Fix Flucon treat bacterial fin rot?
Fix Flucon is an antifungal product. It should not be expected to treat ordinary bacterial fin rot unless a separate susceptible fungal problem is also present.
Can Fix Flucon treat ich, flukes, or other parasites?
No. Fluconazole is an antifungal ingredient and is not a standard treatment for ich, flukes, worms, or other parasitic conditions.
How much Fix Flucon should I use?
The current Fix Flucon listing direction is one pre-dissolved 100 mg tablet per 5 gallons or approximately 19 litres of actual treatment water.
Follow the bottle label received with the product because directions may change.
How long should I treat with Fix Flucon?
The current product direction describes treatment once every 24 hours for five consecutive days.
Discontinue use and reassess the diagnosis if no improvement is noted after five days.
Should I pre-dissolve the tablet?
Yes. Pre-dissolve the required tablet amount in a clean cup of aquarium water, then distribute the solution evenly throughout the treatment tank.
Should I use a hospital tank?
A separate hospital or quarantine tank is strongly recommended. It allows closer observation and limits exposure of healthy fish, plants, invertebrates, and the main aquarium system.
Do I need to remove activated carbon?
Remove activated carbon and other chemical filtration media during treatment because they may reduce the amount of fluconazole available in the water.
Should I switch off the UV sterilizer?
Switch off UV sterilization during treatment unless the current product label specifically directs otherwise.
Can Fix Flucon be used in saltwater aquariums?
Fix Flucon may be used in an appropriately prepared saltwater hospital tank when consistent with the current label.
Avoid treating a reef display containing corals or sensitive invertebrates when a separate treatment system is available.
Is Fix Flucon safe for shrimp, snails, and corals?
Sensitivity can vary between species and systems. Treat affected fish separately rather than exposing shrimp, snails, corals, and other invertebrates.
Can I combine Fix Flucon with other treatments?
Do not combine Fix Flucon with other antifungal, antibacterial, or antiparasitic products unless the labels permit the combination or a qualified aquatic professional recommends it.
What should I do if the fish are not improving?
Discontinue treatment if no improvement appears after five days.
Check water quality, reconsider whether the condition is truly fungal, and seek aquatic veterinary guidance.
How should I store Fix Flucon?
Store the tablets in their original, tightly closed bottle in a cool, dry location protected from direct sunlight, heat, and moisture.
Can Fix Flucon be used for humans or household pets?
No. This product is intended for ornamental aquarium fish. It is not intended for humans, dogs, cats, birds, livestock, or food-producing animals.
Bottom Line
Fix Flucon is a 100 mg fluconazole antifungal tablet for susceptible topical and systemic fungal problems affecting ornamental aquarium fish.
It may be considered for visible cotton-like fungal growth and certain deeper fungal concerns when the organism is sensitive to fluconazole.
The current listing direction is one pre-dissolved tablet per 5 gallons of actual treatment water, administered once daily for five consecutive days.
Discontinue treatment if no improvement appears after five days and reassess whether the condition is truly fungal.
Fix Flucon does not treat bacterial, viral, or parasitic disease and is not intended for humans or food-producing animals.
A separate hospital tank, stable water quality, strong aeration, and correction of the underlying injury or stressor are essential parts of responsible treatment.
More Fish Treatments
Fix Mox (Amoxicillin) 250/500 mg
An antibacterial treatment for certain suspected bacterial concerns, including fin rot, wounds, ulcers, and dropsy-like signs.
Shop Fix Mox →Fix Zole (Metronidazole) 250/500 mg
A treatment used for certain protozoal and anaerobic-sensitive concerns, including Hexamita-related symptoms.
Shop Fix Zole →Fix Doxy (Doxycycline) 100 mg
An antibacterial treatment considered for columnaris-type signs and certain respiratory or systemic bacterial concerns.
Shop Fix Doxy →Fix Zithro (Azithromycin) 250 mg
An antibacterial treatment considered for fin damage, gill concerns, columnaris-type signs, and other susceptible bacterial problems.
Shop Fix Zithro →Fix Cin (Clindamycin) 150 mg
An antibacterial treatment used for certain skin, mouth, wound, and soft-tissue concerns in ornamental aquarium fish.
Shop Fix Cin →Fix Sulfa (SMZ/TMP) 960 mg
A dual-ingredient antibacterial treatment used for a range of suspected bacterial concerns in ornamental aquarium fish.
Shop Fix Sulfa →Fix Pen (Penicillin) 500 mg
A penicillin treatment considered for certain susceptible Gram-positive bacterial concerns in ornamental fish.
Shop Fix Pen →Fix Flex (Cephalexin) 250/500 mg
An antibacterial treatment used for certain fin, skin, wound, and soft-tissue concerns in ornamental aquarium fish.
Shop Fix Flex →Fix Flox (Ciprofloxacin) 500 mg
An antibacterial treatment considered for persistent fin damage, ulcers, columnaris-type patches, and septicemia-like signs.
Shop Fix Flox →Browse All Fish Treatments
Explore the complete Fish Treatments Collection for antifungal, antibacterial, and related aquarium-care products.
Explore the Collection →Guides and Care Tips
Visit the aquarium-care blog for practical treatment guides, water-quality advice, quarantine information, and fish-health tips.
Visit the Blog →Transparency & Verification
How Product Information Is Verified
Who is responsible for this page: The store editorial team responsible for reviewing and maintaining product information.
Verification snapshot: This page was prepared from available product specifications and current Fix Flucon listing information and should be checked against the physical bottle label before publishing.
How We Verify Product Information
Label-First Accuracy
The physical bottle label is treated as the primary source for the amount, treatment duration, storage instructions, and warnings.
Specification Validation
The active ingredient, tablet strength, bottle count, intended species, and manufacturer information are checked against available product specifications.
Consistency Checks
Product content is reviewed for consistent strength information, treatment directions, storage details, and safety language throughout the page.
Updates
The page should be updated whenever the product label, packaging, bottle count, manufacturer information, or directions change.
See something that does not match the product received? Please contact us so the information can be reviewed and updated.
Fish Penicillin | Antibiotic for Aquarium Fish
Regular price $34.99 Save $-34.99Fish Penicillin 500mg | Antibiotic for Aquarium Fish
Fix Pen is an antibacterial treatment for ornamental aquarium fish and non-food pet birds.
Each tablet contains 500 mg of Penicillin V Potassium and is manufactured in the United States by Aqua Soma Labs.
Fix Pen is available in bottles containing 30 or 60 tablets with clearly printed expiration dates.
Aquarium keepers may know this product under older names such as Fish Pen, Fish Pen Forte, Aqua Pen, or FISHBIOTIC Penicillin.
These were names associated with discontinued Thomas Labs products, while Fix Pen is the current Aqua Soma Labs replacement.
Aquarium keepers may consider penicillin tablets when ornamental fish show suspected bacterial signs such as fin and tail rot, mouth rot, infected wounds, pop-eye, cloudy eyes, open sores, ulcers, reddened skin, or columnaris-type lesions with a cotton-wool appearance.
Penicillin V acts on the cell walls of certain susceptible bacteria and is generally associated with activity against Gram-positive bacteria and some Gram-negative organisms.
Fix Pen provides a consistent 500 mg tablet strength that can be dissolved in aquarium water or divided for a smaller treatment system.
The same tablets may be considered for non-food pet birds only under direct avian veterinary guidance.
Choose the 30-count bottle for a single hospital tank or occasional use, or the 60-count bottle for larger aquarium collections, multi-tank operations, or a veterinarian-directed aviary treatment plan.
Begin treatment at the first signs of a suspected bacterial concern. Symptoms differ between fish and birds, so review the separate lists below.
Fish-Specific Symptoms
- Fin and tail rot with frayed or deteriorating fins
- Mouth rot
- Infected wounds
- Pop-eye or bulging eyes
- Cloudy eyes
- Columnaris-type lesions with a cotton-wool appearance
- Open sores, ulcers, or reddened skin
- Reduced appetite, lethargy, or hiding
Bird-Specific Symptoms Under Veterinary Guidance
- Respiratory signs with labored breathing
- Soft-tissue concerns linked by a veterinarian to bacteria
- Fluffed-up feathers
- Lethargy or inactivity
- Decreased appetite
- Other symptoms specifically evaluated by an avian veterinarian
For birds, only use Fix Pen when an avian veterinarian has recommended penicillin for a specific condition and has determined the appropriate amount, administration method, frequency, and duration.
Stable water quality, appropriate nutrition, good housing, low stress, and careful observation remain essential parts of fish and bird care.
Penicillin does not treat viral problems, and unnecessary antibacterial use may reduce treatment effectiveness over time.
Same-day dispatch: In-stock orders placed before 1:30 p.m. CT, Monday through Friday, ship from our United States warehouse through USPS or UPS.
Fish Pen Forte vs Fix Pen: What Changed?
If you previously purchased Thomas Labs Fish Pen, Fish Pen Forte, Aqua Pen, or FISHBIOTIC Penicillin, here is what remains the same and what has changed.
Same Penicillin Formula
Fix Pen contains Penicillin V Potassium at 500 mg per tablet, matching the familiar strength associated with Fish Pen and Fish Pen Forte.
New Manufacturer
Fix Pen is manufactured in the United States by Aqua Soma Labs and replaces the discontinued Thomas Labs product line.
Same Dissolvable Tablet Form
The tablet can be dissolved in aquarium water or divided for smaller treatment volumes according to the current bottle label.
30-Count and 60-Count Bottles
Choose the bottle size that fits a single hospital tank, repeat treatment, multi-tank aquarium setup, or veterinarian-directed aviary plan.
Benefits of Fix Pen for Fish & Birds
Targeted Gram-Positive Bacterial Coverage
Penicillin is commonly considered when a susceptible Gram-positive bacterial component is suspected in fin damage, mouth rot, sores, ulcers, pop-eye, or cloudy eyes.
Made in the United States
Fix Pen is manufactured in the United States by Aqua Soma Labs and supplied with clearly printed strength and expiration information.
Consistent 500 mg Tablets
Each tablet provides a fixed 500 mg amount of Penicillin V Potassium, making treatment-water calculations easier across different aquarium volumes.
Common Aquarium Use Cases
Aquarium keepers may consider Fix Pen for suspected bacterial fin damage, infected wounds, flexibacter-type concerns, ulcers, and other symptoms where a susceptible bacterial cause is likely.
Freshwater and Saltwater Compatible
Fix Pen may be used in properly prepared freshwater or saltwater treatment tanks according to the current product label.
Quarantine-Friendly and Biofilter Aware
A separate hospital tank helps protect the display aquarium's beneficial bacteria, sensitive invertebrates, and healthy tank mates.
Vet-Directed Option for Pet Birds
Penicillin may be used for non-food pet birds only when an avian veterinarian has diagnosed the problem and established the appropriate treatment plan.
Usage Guidelines & Instructions
Quick Usage Summary for Fish
Use one 500 mg tablet per 20 gallons or approximately 76 litres of treatment water.
Repeat every 24 hours and perform a partial water change between treatments.
Continue for 5 to 10 days and discontinue use if no improvement is seen after five days.
Set Up a Separate Treatment Area
Treat affected fish in a hospital or quarantine tank whenever possible.
This limits exposure of healthy tank mates and makes it easier to monitor treatment response, ammonia, nitrite, temperature, and oxygen levels.
Remove activated carbon and other chemical filtration media and switch off UV sterilization during treatment.
Directions for Fish Aquariums
Dissolve one 500 mg tablet in a clean cup of aquarium water.
Add the dissolved mixture evenly throughout the treatment tank for every 20 gallons or approximately 76 litres of actual treatment water.
Calculate the real water volume after accounting for substrate, decorations, equipment, and fill level.
Repeat Every 24 Hours
Repeat treatment once every 24 hours according to the current bottle label.
Perform a partial water change between treatments to maintain suitable water quality.
Continue for 5 to 10 Days
Continue treatment for the complete recommended period, even when the fish begin to improve, unless a qualified professional advises otherwise.
Stopping treatment too early may allow the suspected bacterial problem to return.
Stop if There Is No Improvement
If no improvement is seen after five days, discontinue treatment and reassess the water quality and likely cause.
Seek aquatic veterinary or fish-health guidance if the fish become worse or develop severe distress.
Maintain Water Quality
Maintain strong aeration and stable temperature throughout treatment.
Test ammonia and nitrite regularly because antibacterial treatment may disturb beneficial filtration.
Pet Birds Under Veterinary Guidance Only
Do not use the aquarium-water chart to calculate an amount for birds.
An avian veterinarian must determine the correct amount according to species, weight, diagnosis, administration method, frequency, and duration.
Fix Pen Amounts by Aquarium Size
| Tank volume | Penicillin per use | 500 mg tablets |
|---|---|---|
| 10 gallons (38 L) | 250 mg | ½ tablet or the equivalent measured dissolved portion |
| 20 gallons (76 L) | 500 mg | 1 tablet |
| 40 gallons (151 L) | 1,000 mg | 2 tablets |
| 60 gallons (227 L) | 1,500 mg | 3 tablets |
| 75 gallons (284 L) | Approximately 1,875 mg | Approximately 4 tablets |
What to Expect During Treatment
Days 1 to 2
Fish may hide, eat less, or produce slightly cloudy treatment water. Maintain the treatment schedule and keep aeration strong.
Days 3 to 5
Look for sores and red areas that stop spreading, returning appetite, improved activity, and steadier breathing.
Days 5 to 10
Complete the recommended treatment. Afterward, perform a partial water change and restore activated carbon to help clear remaining treatment.
What You Need for Treatment
- A separate hospital or quarantine tank
- A suitable aquarium heater
- An air stone or established sponge filter
- An ammonia and nitrite test kit
- A suitable water conditioner or dechlorinator
- A small net for gentle transfer
- A clean cup for dissolving and measuring the treatment
Pro Tip: Dose according to the actual treated water volume rather than the aquarium's advertised capacity. Gravel, rocks, decorations, equipment, and the fill level reduce the amount of water inside the tank.
How Fix Pen Works
Each Fix Pen tablet contains 500 mg of Penicillin V Potassium.
Penicillin V works by interfering with the cell walls of certain susceptible bacteria.
It is generally associated with activity against certain Gram-positive bacteria and some Gram-negative organisms when used as directed in ornamental fish care.
The treatment is most appropriate when a susceptible bacterial cause is likely and should not be expected to treat fungal, viral, or parasitic conditions.
Each tablet also contains standard inactive ingredients that hold the tablet together during storage and allow it to break apart and disperse in aquarium water.
Use in non-food pet birds must follow the exact diagnosis and instructions of an avian veterinarian.
Safety and Tank Notes
When used according to the current label, Fix Pen usually causes no problems in ornamental aquarium fish.
Unnecessary use, inaccurate amounts, combining multiple treatments, or prolonged treatment may increase stress and antibacterial resistance.
Fish
Fish may temporarily hide, eat less, or appear mildly lethargic during treatment.
If severe distress develops, including rapid gill movement, surface gasping, loss of balance, rolling, or remaining on the bottom, stop treatment, increase aeration, and perform an appropriate partial water change.
Birds
Use Fix Pen in non-food pet birds only under avian veterinary guidance.
If a bird becomes unusually lethargic, stops eating, develops breathing difficulty, or appears significantly worse, discontinue use and contact the veterinarian.
Invertebrates
Do not use Fix Pen in display tanks containing shrimp, snails, corals, or other sensitive invertebrates whenever a separate treatment tank is available.
Penicillin may harm sensitive species or disturb the aquarium ecosystem.
Biofilter Awareness
Antibacterial treatment may affect beneficial filtration bacteria.
Monitor ammonia and nitrite closely and perform partial water changes whenever necessary.
Filtration During Treatment
Remove activated carbon and other chemical filtration media and switch off UV sterilization during treatment.
Restore normal filtration after treatment is complete.
Do Not Mix Treatments
Do not combine Fix Pen with other aquarium or bird treatments unless a qualified veterinarian specifically recommends the combination.
Important Safety Note
Fix Pen is intended for ornamental aquarium fish and non-food pet birds only.
It is not intended for animals raised for food.
Store tablets in their original, tightly closed container in a cool, dry place protected from direct sunlight, excessive heat, and moisture.
Keep out of reach of children and animals.
Always follow the directions printed on the current product label.
Shipping & Returns
Shipping Policy
Orders ship from our United States warehouse within one business day through USPS or UPS.
In-stock orders placed before 1:30 p.m. CT, Monday through Friday, may ship the same business day.
Shipping rates and estimated delivery times are calculated at checkout.
Review Shipping Policy →Refund Policy
If there is an issue with your order, eligible products may be returned or exchanged within 30 days according to the current store guidelines.
Review the complete refund policy before returning any product.
Review Refund Policy →Frequently Asked Questions
What is Fix Pen used for?
Fix Pen contains Penicillin V Potassium and is intended for certain suspected bacterial problems in ornamental aquarium fish, including fin and tail rot, mouth rot, infected wounds, ulcers, pop-eye, cloudy eyes, and some columnaris-type lesions.
Use in non-food pet birds should occur only under avian veterinary guidance.
What is the difference between Fish Pen Forte and Fix Pen?
Fix Pen is the current Aqua Soma Labs replacement for discontinued Thomas Labs Fish Pen and Fish Pen Forte products. It provides the same 500 mg Penicillin V Potassium tablet strength with updated packaging.
Is Fix Pen a replacement for FISHBIOTIC Penicillin or Aqua Pen?
Fix Pen is presented as the current replacement for older FISHBIOTIC Penicillin and Aqua Pen aquarium products.
How soon should I see improvement with Fix Pen?
Improvement may appear within three to five days through sores that stop spreading, improved appetite, increased activity, and steadier breathing.
Discontinue treatment and seek professional advice if the fish worsen or no improvement appears by day five.
Where can I buy penicillin tablets for fish online?
Fix Pen 500 mg tablets can be ordered through this online store in 30-count or 60-count bottles and shipped according to the current store shipping policy.
What is in each Fix Pen tablet?
Each tablet contains 500 mg of Penicillin V Potassium together with standard inactive tablet ingredients.
What is the Fix Pen amount for fish?
The supplied label guideline is one 500 mg tablet per 20 gallons or approximately 76 litres of treatment water.
How long should I treat with Fix Pen?
The supplied instructions describe treatment every 24 hours for 5 to 10 days, with a partial water change between treatments.
Discontinue treatment if no improvement is seen after five days.
Should I treat in the main tank or a hospital tank?
A separate hospital or quarantine tank is strongly preferred. This protects healthy tank mates, sensitive invertebrates, and the display aquarium's established filtration.
Do I need to remove activated carbon or turn off UV?
Remove activated carbon and other chemical filtration media and switch off UV sterilization during treatment because these systems may reduce treatment availability in the water.
Will Fix Pen harm beneficial aquarium bacteria?
Antibacterial treatment may disturb beneficial biological filtration. Use a separate treatment tank whenever possible and monitor ammonia and nitrite closely.
Can Fix Pen be used in saltwater aquariums?
Fix Pen is presented for properly prepared freshwater and saltwater treatment tanks. Use a separate hospital tank when the display system contains corals or sensitive invertebrates.
Is Fix Pen safe for betta fish and small aquariums?
Small aquariums require careful measurement. The supplied rate is one 500 mg tablet per 20 gallons, so a smaller treatment volume requires a proportional amount.
Dissolving one tablet in a measured volume and adding the appropriate fraction may be more accurate than dividing the tablet by hand.
Can I use Fix Pen in a planted tank or with shrimp and snails?
Treat affected fish in a separate hospital tank whenever possible. Penicillin may disturb the display aquarium and may harm shrimp, snails, or other sensitive invertebrates.
Can Fix Pen treat fungal, viral, or parasitic infections?
Fix Pen is an antibacterial product and should not be expected to treat fungal, viral, or parasitic conditions.
Can I combine Fix Pen with other fish treatments?
Do not combine Fix Pen with other aquarium treatments unless a qualified veterinarian specifically recommends the combination.
What should I do after finishing a Fix Pen treatment?
Perform a partial water change, resume normal filtration, restore activated carbon if normally used, and continue monitoring ammonia, nitrite, temperature, and fish behavior.
Can I use Fix Pen for dogs, cats, or chickens?
No. This product is labeled for ornamental aquarium fish and non-food pet birds. It is not intended for dogs, cats, humans, chickens raised for food, or other food-producing animals.
Can I use Fix Pen as penicillin for pet birds?
Fix Pen may be considered for non-food pet birds only under direct avian veterinary guidance. The veterinarian must establish the diagnosis, amount, administration method, frequency, and duration.
How should I store and dispose of Fix Pen tablets?
Store tablets tightly closed in their original container in a cool, dry location protected from direct sunlight, excessive heat, and moisture.
Follow the current product label and applicable local requirements when disposing of unused tablets, treatment water, or filter media. Avoid releasing concentrated treatment into natural waterways.
Bottom Line
Fix Pen is a 500 mg Penicillin V Potassium tablet for certain suspected bacterial problems in ornamental aquarium fish and a veterinarian-directed penicillin option for non-food pet birds.
It is the current Aqua Soma Labs replacement for discontinued Thomas Labs Fish Pen and Fish Pen Forte products.
The supplied aquarium guideline is one 500 mg tablet per 20 gallons or approximately 76 litres of treatment water, repeated every 24 hours for 5 to 10 days with partial water changes between treatments.
Reassess treatment at day five and discontinue use if no improvement is seen.
Fix Pen will not treat fungal, viral, or parasitic conditions and is not intended for animals raised for food.
Use a hospital tank whenever possible and consult an aquatic or avian veterinarian when the diagnosis is uncertain or when treating a bird.
More Fish & Bird Treatments
Fix Mox (Amoxicillin) 250/500 mg
A treatment for fin rot, dropsy, ulcers, infected wounds, and other suspected bacterial concerns in ornamental fish.
Shop Fix Mox →Fix Zole (Metronidazole) 250/500 mg
A treatment for certain anaerobic and protozoal concerns, including Hexamita and hole-in-the-head symptoms.
Shop Fix Zole →Fix Doxy (Doxycycline) 100 mg
A treatment for columnaris, respiratory concerns, and Mycoplasma-related problems in ornamental fish and non-food pet birds.
Shop Fix Doxy →Fix Zithro (Azithromycin) 250 mg
A treatment for fin rot, columnaris, gill disease, and veterinarian-directed avian respiratory concerns.
Shop Fix Zithro →Fix Cin (Clindamycin) 150 mg
A treatment for certain bacterial skin, mouth, wound, and soft-tissue concerns in ornamental aquarium fish.
Shop Fix Cin →Fix Sulfa (SMZ/TMP) 960 mg
A dual-ingredient treatment used for a range of suspected bacterial concerns in ornamental aquarium fish.
Shop Fix Sulfa →Fix Flex (Cephalexin) 250/500 mg
A treatment for fin rot, ulcers, infected wounds, and bacterial skin concerns in ornamental fish and non-food pet birds.
Shop Fix Flex →Fix Flox (Ciprofloxacin) 500 mg
A treatment for suspected bacterial concerns including fin rot, ulcers, columnaris-type patches, and septicemia.
Shop Fix Flox →Browse All Treatments
Explore the complete Fish & Bird Treatments Collection for additional Fix line products and related care options.
Explore the Collection →Guides and Care Tips
Visit the Fish & Bird Care Blog for practical aquarium guides, water-care information, and treatment tips.
Visit the Blog →Transparency & Verification
How Product Information Is Verified
Who is responsible for this page: The store editorial team responsible for reviewing and maintaining product information.
Verification snapshot: This page is written from the current product label for this item and reviewed for accuracy and consistency before publishing.
How We Verify Product Information
Label-First Accuracy
Directions, treatment duration, storage information, and warnings are taken from the current product label.
Specification Validation
The active ingredient, tablet strength, bottle counts, and manufacturer information are cross-checked against available product specifications.
Consistency Checks
Product content is reviewed for consistent strength information, directions, storage details, and safety language throughout the page.
Updates
Pages are updated when product labels, packaging, tablet counts, manufacturer details, or directions change.
See something that does not match the product you received? Please contact us so the information can be reviewed and updated.
Erythromycin Fish Antibiotic Powder for Fin & Tail Rot – 200 Gallons
Regular price $49.99 Save $-49.99Erythromycin Fish Antibiotic Powder for Fin & Tail Rot – 200 Gallons
Erythromycin Fish Antibiotic Powder for Fin & Tail Rot – 200 Gallons is a concentrated erythromycin aquarium treatment intended primarily for label-listed gram-positive bacterial concerns in ornamental fish. This size provides label-directed coverage for up to 200 gallons when measured and applied according to the current product label.
Key Aquarium Treatment Features
- Supports label-directed care for fin rot, tail rot, mouth sores, cloudy eyes and popeye.
- Also listed for selected aquarium concerns described as molly disease, tetra disease, wasting and swollen belly.
- The label includes guidance for cyanobacteria or red-slime concerns in aquarium systems.
Label-Listed Fish Health Concerns
This product may be considered when the visible signs and the current label are consistent with concerns such as:
- Fin rot
- Tail rot
- Mouth sores
- Eye sores
- Cloudy eyes
- Protruding eyes
- Popeye
- Molly disease
- Tetra disease
- Cyanobacteria
- Red slime
- Swollen belly
- Wasting disease
- Bacterial infection
Visible symptoms do not confirm a diagnosis. Similar signs may result from poor water quality, parasites, fungus, injury, toxins or environmental stress. Correct the aquarium environment and seek qualified aquatic guidance when the cause is uncertain.
Dosage and Application Directions
- Condition the aquarium water before measuring the treatment.
- Dose 1/4 teaspoon per 20 gallons of actual aquarium water.
- Repeat after 24 hours and complete a partial water change between treatments.
- Continue the extended bath for at least 5 days and no longer than 10 days, according to the label.
- Stop and reassess if no improvement is visible within 5 days. Allow several days before introducing a different medication.
Label priority: Always compare these listing details with the instructions printed on the bottle you receive. The physical product label controls the amount, frequency, duration, compatibility and storage requirements.
Prepare the Treatment Aquarium
- Calculate dosage from the aquarium’s actual water volume, not its advertised capacity.
- Use a separate hospital or quarantine tank whenever practical.
- Test ammonia and nitrite before treatment and throughout the complete course.
- Remove activated carbon, UV or other equipment only when the current label directs you to do so.
- Maintain stable temperature and strong aeration while observing the fish closely.
Avoid combining erythromycin with other treatments unless the current labels permit it or a qualified aquatic professional specifically directs the combination.
Coverage and Product Format
The concentrated powder format is designed for accurate measuring in a controlled treatment system. This package treats up to 200 gallons at the label-directed rate, making the coverage easy to compare with your hospital tank, quarantine aquarium or ornamental pond treatment volume.
wepetverse.com Product Information
wepetverse.com organizes aquarium treatments by active ingredient, intended use and total gallon coverage so fish keepers can compare products without relying only on brand nicknames. Review the current label, calculate actual water volume and select treatment according to the likely cause rather than symptoms alone.
Important Safety Notice
For ornamental aquarium and ornamental pond fish only. Not for human use or consumption. Do not use on fish intended for human consumption. Keep tightly closed and protected from children, animals, moisture, excessive heat and direct light. Use only as directed and consult a qualified aquatic veterinarian or fish-health professional when the condition is severe, recurring or unclear.
Fish Clindamycin 150mg (Fish Cin) | Fish Antibiotic
Regular price $79.99 Save $-79.99Fish Clindamycin 150mg (Fish Cin) | Fish Antibiotic
Fix Cin is an antibacterial treatment from Aqua Soma Labs for ornamental aquarium fish.
Each capsule contains 150 mg of clindamycin in a dissolvable powder. Aquarium keepers use it to help manage suspected bacterial problems such as fin and tail rot, mouth rot or cotton-mouth, skin ulcers, and slow-healing lesions.
The bottle contains 100 capsules, making it suitable for larger aquariums, multi-tank fish rooms, quarantine systems, or repeat treatment plans.
If you previously purchased Thomas Labs Fish Cin or Aqua-Cin, Fix Cin is the current replacement and provides clindamycin at the same 150 mg capsule strength.
Aquarium keepers may consider it when fish show fin and tail deterioration, mouth rot or cotton-mouth, bacterial dropsy-like symptoms, skin ulcers, recurring lesions, swim bladder concerns, or other suspected internal bacterial problems.
The capsule opens easily so the powder can be dissolved and distributed throughout a separate hospital or quarantine tank.
Use Fix Cin at the first signs of suspected bacterial stress, alongside clean water, stable temperature, strong aeration, and careful observation.
Fish Symptoms to Watch For
- Clamped, frayed, or deteriorating fins
- Fin and tail rot
- Reddened areas or red streaking
- Open sores, skin ulcers, or slow-healing lesions
- Cottony-looking mouth damage or mouth rot
- Listlessness or lethargy
- Persistent appetite loss
- Possible bacterial swim bladder or internal concerns
Treating early, together with clean water and strong aeration, helps protect the rest of the aquarium while the affected fish recovers.
If the main aquarium contains shrimp, snails, corals, or other sensitive invertebrates, move affected fish to a separate treatment tank.
Same-day dispatch: Qualifying orders placed before 1:30 p.m. CT, Monday through Friday, ship directly from our United States warehouse.
Fish Cin vs Fix Cin: What Changed?
If you previously purchased Thomas Labs Fish Cin or Aqua-Cin, here is what changed and what remains the same.
Same Clindamycin Formula
Fix Cin contains clindamycin hydrochloride at 150 mg per capsule, matching the strength associated with Thomas Labs Fish Cin.
New Manufacturer
Fix Cin is made in the United States by Aqua Soma Labs and replaces discontinued Thomas Labs Fish Cin and Aqua-Cin product lines.
Same Dissolvable Powder Form
The capsule opens so the clindamycin powder can be mixed into aquarium water in the same familiar treatment format.
100-Count Bottle
The 100-capsule supply is practical for larger treatment tanks, repeat treatment, quarantine systems, and multi-tank aquarium keepers.
Benefits of Fix Cin for Fish
Support for Common Bacterial Aquarium Problems
Fix Cin is commonly considered when bacterial stress appears through fin damage, mouth irritation, ulcers, lesions, or slow-healing wounds.
Freshwater and Saltwater Treatment
Aquarium keepers may use Fix Cin in properly prepared freshwater or saltwater hospital tanks according to the current label directions.
Helpful for Lesions and Wound-Type Concerns
Clindamycin may be considered when ornamental fish display redness, open sores, frayed fins, recurring lesions, or other suspected bacterial skin and soft-tissue problems.
Support for Internal Bacterial Concerns
Fix Cin may also be used in a treatment setup when appetite loss, low activity, digestive-type changes, or swim bladder symptoms may be connected with an internal bacterial problem.
Consistent 150 mg Capsules
Each capsule provides a fixed 150 mg amount of clindamycin, making aquarium-volume calculations easier and more repeatable.
100 Capsules for Larger Setups
The 100-count bottle is practical for larger aquariums, dedicated quarantine tanks, repeat treatment, and multi-tank fish rooms.
Hospital-Tank Friendly
Treatment in a separate hospital tank keeps the product where it is needed and reduces unnecessary exposure of the display aquarium and healthy tank mates.
Usage Guidelines & Instructions
Set Up a Separate Treatment Tank
Move affected fish to a dedicated hospital or quarantine tank whenever possible.
This makes treatment and observation easier while reducing unnecessary exposure of healthy tank mates.
Remove activated carbon and other chemical filtration media and switch off ultraviolet sterilization during treatment.
Increase aeration and maintain stable temperature.
Dose According to Aquarium Water Volume
Add one 150 mg capsule per 10 gallons or approximately 38 litres of treatment water.
Open the capsule and mix the powder in a small cup of aquarium water before adding it evenly throughout the treatment tank.
Repeat Every 24 Hours
Repeat the treatment once every 24 hours according to the current bottle label.
Perform Partial Water Changes
Perform a partial water change between treatments to support suitable water quality.
Monitor ammonia, nitrite, temperature, oxygen levels, and fish behavior throughout treatment.
Continue for 5 to 10 Days
Continue treatment for 5 to 10 days according to the severity of the suspected bacterial problem and the current product label.
Complete the recommended treatment period unless the fish develop severe distress or a qualified aquatic professional advises otherwise.
Stop if There Is No Improvement by Day Five
If no improvement appears within five days, discontinue use and reassess the likely cause.
Seek guidance from an aquatic veterinarian or fish-health professional, especially when symptoms worsen.
Clear the Harmless Yellow Tint After Treatment
Treatment water may develop a harmless yellow tint.
After treatment, change approximately 20% of the water and restore activated carbon until the water clears.
Fix Cin Amounts by Aquarium Size
| Tank volume | Clindamycin per use | 150 mg capsules |
|---|---|---|
| 10 gallons (38 L) | 150 mg | 1 capsule |
| 20 gallons (76 L) | 300 mg | 2 capsules |
| 30 gallons (114 L) | 450 mg | 3 capsules |
| 40 gallons (151 L) | 600 mg | 4 capsules |
| 55 gallons (208 L) | Approximately 825 mg | 5 to 6 capsules |
What to Expect During Treatment
Days 1 to 2
Fish may hide or eat less, and the water may develop a harmless yellow tint. Maintain strong aeration and continue monitoring water quality.
Days 3 to 5
Look for sores and red areas that stop spreading, fins that begin holding their shape, returning appetite, and improved activity.
Days 5 to 10
Complete the recommended treatment period. Afterward, change approximately 20% of the water and restore activated carbon to help clear remaining treatment and discoloration.
What You Need for Treatment
- A separate hospital or quarantine tank
- A suitable aquarium heater
- An air stone or established sponge filter
- An ammonia and nitrite test kit
- A suitable water conditioner or dechlorinator
- A small net for gentle fish transfer
- A clean cup for mixing the capsule powder
- Activated carbon for use after treatment
Pro Tip: Antibacterial treatments may affect biological filtration in some aquarium setups. Test ammonia and nitrite regularly, maintain strong aeration, and use a separate treatment tank whenever possible.
How Fix Cin Works
Each Fix Cin capsule contains 150 mg of clindamycin in a dissolvable powder.
Clindamycin works by slowing the growth of certain susceptible bacteria, giving affected ornamental fish a better opportunity to recover when treatment is combined with clean water and appropriate aquarium care.
Treatment success depends on the organism involved, the condition of the fish, and the stability of the treatment system.
Fix Cin is best considered when a bacterial problem is suspected rather than for fungal, parasitic, or viral conditions.
The capsule shell and standard inactive ingredients help hold the powder together, maintain stability during storage, and allow the contents to disperse when mixed into aquarium water.
The complete inactive ingredient breakdown may not be printed on the retail label.
Safety and Tank Notes
When used according to the current label, Fix Cin usually causes no problems in ornamental aquarium fish.
Incorrect amounts, combining multiple treatments, unnecessarily prolonged use, or repeat treatment without confirming the cause may increase the risk of unwanted reactions and antibacterial resistance.
Possible Fish Reactions
Fish may temporarily hide, appear mildly lethargic, eat less, or show temporary treatment-water discoloration.
Stop Treatment and Act Quickly If
Stop treatment if fish develop rapid gill movement, loss of balance, surface gasping, rolling, severe weakness, or remain on the bottom.
Increase aeration and perform an appropriate partial water change.
Support Water Quality
Maintain strong aeration, test ammonia and nitrite, and perform partial water changes as needed between treatments.
Filtration During Treatment
Remove activated carbon and other chemical filtration media and switch off UV sterilization during treatment.
Activated carbon may be restored after treatment to help clear discoloration and remaining product.
Invertebrates
If the display aquarium contains shrimp, snails, corals, or other sensitive invertebrates, move affected fish to a separate hospital tank.
Do Not Mix Treatments
Do not combine Fix Cin with other aquarium treatments unless a qualified professional specifically recommends the combination.
Important Warnings & Precautions
Aquarium use only: Fix Cin is intended for ornamental aquarium fish only.
Not for food fish: Do not use this product on animals raised for human consumption.
Storage: Keep capsules in their original, tightly closed container at 59–86°F or 15–30°C.
Store in a cool, dry location protected from moisture and direct sunlight.
Keep out of reach of children and animals.
Discontinue if no improvement: Stop treatment if no improvement appears after five days and reassess the likely cause.
Shipping & Returns
Shipping Policy
Orders ship from our United States warehouse within one business day through USPS or UPS.
Qualifying orders placed before 1:30 p.m. CT, Monday through Friday, may ship the same business day.
Shipping rates and estimated delivery times are calculated at checkout.
Review Shipping Policy →Refund Policy
If there is an issue with your order, eligible products may be returned or exchanged within 30 days according to the current store guidelines.
Review the complete refund policy before returning any item.
Review Refund Policy →Frequently Asked Questions
What is Fix Cin used for in fish?
Fix Cin contains clindamycin and is intended for certain suspected bacterial problems in ornamental aquarium fish, including fin and tail rot, mouth rot, ulcers, lesions, open sores, and soft-tissue concerns.
What is the difference between Fish Cin and Fix Cin?
Fix Cin is the current Aqua Soma Labs replacement for discontinued Thomas Labs Fish Cin. It provides the same 150 mg clindamycin capsule strength in updated packaging.
Is Fix Cin a replacement for Aqua-Cin?
Fix Cin is presented as the current replacement for older Aqua-Cin clindamycin products used by aquarium keepers.
Where can I buy clindamycin for fish online?
Fix Cin 150 mg capsules can be ordered through this online store in a 100-count bottle and shipped according to the current store shipping policy.
What is the active ingredient in Fix Cin?
Each capsule contains 150 mg of clindamycin in a dissolvable powder.
How do I know if my fish might need clindamycin?
Possible bacterial signs include frayed fins, mouth damage, red streaking, open sores, ulcers, recurring lesions, appetite loss, and lethargy.
Similar symptoms may result from poor water quality, parasites, fungal conditions, injury, or other causes, so professional assessment is recommended when the diagnosis is uncertain.
Can Fix Cin treat fungal, parasitic, or viral problems?
Fix Cin is an antibacterial product. It should not be expected to treat fungal, parasitic, or viral conditions.
Can I use Fix Cin in my main community tank?
A separate hospital or quarantine tank is preferred. This protects healthy tank mates and reduces disruption to the display aquarium's biological filtration.
Is Fix Cin safe for saltwater fish or reef tanks?
Fix Cin may be used in a properly prepared saltwater hospital tank. Do not treat a reef display containing corals or sensitive invertebrates when a separate treatment system is available.
What is the recommended amount for fish?
The supplied guideline is one 150 mg capsule per 10 gallons or approximately 38 litres of treatment water.
How long should I treat with Fix Cin?
The supplied directions describe treatment every 24 hours for 5 to 10 days, with partial water changes between treatments.
What if my fish shows no improvement after five days?
Discontinue treatment and reassess the water quality and likely cause. Seek aquatic veterinary guidance, especially when symptoms become worse.
Will Fix Cin affect beneficial aquarium bacteria?
Antibacterial treatments may disturb biological filtration. Use a separate treatment tank and monitor ammonia and nitrite closely.
Can I mix Fix Cin with other treatments?
Do not combine Fix Cin with other aquarium treatments unless a qualified professional specifically recommends the combination.
Can I use Fix Cin as a preventive treatment?
Routine preventive use is not recommended. Treatment should be based on observed symptoms, the current bottle label, and professional guidance when the diagnosis is uncertain.
Is Fix Cin safe for betta fish and small aquariums?
Small treatment tanks require careful measurement. The supplied guideline is one 150 mg capsule per 10 gallons. Follow the current label or consult an aquatic professional rather than estimating.
Is Fix Cin the same as fish clindamycin?
Fish clindamycin is a common search term for clindamycin capsules labeled for ornamental aquarium fish. Fix Cin supplies clindamycin in a 150 mg capsule.
Is there a Fix Cin 300 mg version?
This Fix Cin product is supplied in a 150 mg capsule strength. A total amount of 300 mg would equal two 150 mg capsules according to the aquarium-volume guide.
How should I store and dispose of Fix Cin capsules?
Store capsules tightly closed in their original container at 59–86°F or 15–30°C in a cool, dry location protected from sunlight and moisture.
Follow the product label and applicable local requirements when disposing of unused capsules, treatment water, or filter media. Avoid releasing concentrated treatment into natural waterways.
How soon should I see improvement?
Improvement may become visible within three to five days through sores that stop spreading, improved fin condition, returning appetite, and increased activity.
Stop treatment and seek professional guidance if the fish become worse or no improvement appears by day five.
More Fish & Bird Treatments
Fix Mox (Amoxicillin) 250/500 mg
A treatment for fin rot, dropsy, ulcers, and other suspected bacterial concerns in ornamental fish.
Shop Fix Mox →Fix Zole (Metronidazole) 250/500 mg
A treatment for certain anaerobic and protozoal concerns, including Hexamita and hole-in-the-head symptoms.
Shop Fix Zole →Fix Doxy (Doxycycline) 100 mg
A treatment for columnaris, respiratory concerns, and Mycoplasma-related problems in ornamental fish and non-food pet birds.
Shop Fix Doxy →Fix Zithro (Azithromycin) 250 mg
A treatment for fin rot, columnaris, gill disease, and veterinarian-directed avian respiratory concerns.
Shop Fix Zithro →Fix Sulfa (SMZ/TMP) 960 mg
A dual-ingredient treatment used for a range of suspected bacterial concerns in ornamental aquarium fish.
Shop Fix Sulfa →Fix Pen (Penicillin) 500 mg
A treatment for certain suspected bacterial problems in ornamental fish and non-food pet birds.
Shop Fix Pen →Fix Flex (Cephalexin) 250/500 mg
A treatment for fin rot, ulcers, infected wounds, and bacterial skin concerns in ornamental fish.
Shop Fix Flex →Fix Flox (Ciprofloxacin) 500 mg
A treatment for suspected bacterial concerns including fin rot, ulcers, columnaris-type patches, and septicemia.
Shop Fix Flox →Browse All Treatments
Explore the complete Fish & Bird Treatments Collection for more Fix line products and related care options.
Explore the Collection →Guides and Treatment Tips
Visit the Fish & Bird Treatments Blog for practical aquarium guides, water-care information, and treatment tips.
Visit the Blog →Transparency & Verification
How Product Information Is Verified
Who is responsible for this page: The store editorial team responsible for reviewing and maintaining product information.
Verification snapshot: This page is written from the current product label for this item and reviewed for accuracy and consistency before publishing.
How We Verify Product Information
Label-First Accuracy
Directions, treatment duration, storage information, and warnings are taken from the current product label.
Specification Validation
The active ingredient, capsule strength, bottle count, and manufacturer information are cross-checked against available product specifications.
Consistency Checks
Product content is reviewed for consistent directions, strength information, storage details, and safety language throughout the page.
Updates
Pages are updated when product labels, packaging, capsule counts, manufacturer details, or directions change.
See something that does not match the product you received? Please contact us so the information can be reviewed and updated.
Fish Ciprofloxacin 500mg (Fish cipro) | Fish Antibiotic
Regular price $44.99 Save $-44.99Fish Ciprofloxacin 500mg (Fish cipro) | Fish Antibiotic
Fish Flox (Fix Flox) from Aqua Soma Labs is an antibacterial treatment for ornamental aquarium fish and non-food pet birds.
Each capsule contains 500 mg of ciprofloxacin, which works in treatment water to help manage suspected bacterial problems such as persistent fin and tail rot, columnaris-type patches, and ulcer-like sores when used as directed.
In the aquarium community, it is still commonly called Fish Flox, Fish Flox Forte, Aqua Cipro, fish cipro, or fish ciprofloxacin 500 mg.
Fix Flox from the Aqua Soma Labs Fix range is the current online replacement for discontinued Thomas Labs Fish Flox and Aqua-Cipro 500 mg products.
Aquarium keepers who previously used Fish Flox Forte or Aqua Cipro will recognize the same 500 mg capsule strength under updated Fix-brand labeling.
Fix Flox may be used to help manage persistent fin and tail rot, columnaris-type patches, ulcer-like sores, red sores, hemorrhagic septicemia, bacterial swim bladder concerns, and dropsy-like swelling.
These concerns may involve susceptible organisms such as Aeromonas, Pseudomonas, Vibrio, or Flavobacterium.
Reef keepers may also use ciprofloxacin in a separate hospital tank for suspected bacterial problems affecting anemones, including repeated deflation or tissue deterioration.
Fix Flox is available in 30-count and 60-count bottles with clearly printed expiration dates.
Choose the bottle size that fits your setup, whether maintaining one hospital tank, several community aquariums, or following an avian veterinarian's ciprofloxacin plan for a non-food pet bird.
Begin treatment when early signs of bacterial stress appear. Signs can differ between fish and birds, so the lists below separate the symptoms by species.
Fish-Specific Symptoms
- Fin and tail rot with frayed or deteriorating fins
- Ulcer-like sores or open wounds
- Red sores or red streaking on the body
- Dropsy-like swelling
- Columnaris-type patches
- Cloudy body patches that remain after water quality improves
- Lethargy, appetite loss, or a rapid decline in activity
Bird Signs Under Veterinary Guidance
- Fluffed-up feathers
- Lethargy or reduced activity
- Decreased appetite
- Loose or changed droppings
- Labored or difficult breathing
- Any sudden change linked by a veterinarian to a bacterial problem
For birds, only use Fix Flox when an avian veterinarian has recommended ciprofloxacin for a specific condition and has established the appropriate amount, frequency, and duration.
Addressing a suspected bacterial problem early, together with stable water quality, good aeration, appropriate nutrition, and suitable housing, gives fish and birds a better opportunity to recover.
Same-day dispatch: Qualifying orders placed before 1:30 p.m. CT, Monday through Friday, ship from our United States warehouse through USPS or UPS.
Fish Flox vs Fix Flox: What Changed?
If you previously purchased Thomas Labs Fish Flox, Fish Flox Forte, or Aqua Cipro, here is what changed and what stayed the same.
Same Ciprofloxacin Strength
Fix Flox contains the same 500 mg of ciprofloxacin per capsule associated with Fish Flox Forte and Aqua Cipro.
New Manufacturer
Fix Flox is made in the United States by Aqua Soma Labs, replacing the discontinued Thomas Labs product line.
Same Capsule Form
The capsule can be opened and the powder dissolved in aquarium water, matching the format used by previous Fish Flox products.
30-Count and 60-Count Options
Choose a 30-count bottle for a smaller setup or occasional use, or a 60-count bottle for larger aquarium collections and longer treatment plans.
Benefits of Fix Flox for Fish & Birds
Wide Bacterial Coverage
Ciprofloxacin is generally described as active against many Gram-negative bacteria and certain Gram-positive organisms affecting ornamental fish.
Made in the United States
Fix Flox is manufactured in the United States by Aqua Soma Labs and supplied with clearly printed capsule strength and expiration information.
Helps Manage Stubborn Aquarium Problems
Aquarium keepers may choose Fix Flox for persistent fin rot, columnaris-type patches, bacterial gill irritation, ulcer-like sores, red streaking, septicemia, or bacterial dropsy-like swelling.
Consistent 500 mg Capsules
Each capsule contains a fixed 500 mg amount, making aquarium-volume calculations straightforward in a properly prepared hospital tank.
Easy to Prepare
Open the capsule, mix the powder in a clean cup of aquarium water, and distribute the prepared treatment evenly throughout the hospital tank.
Freshwater, Saltwater & Avian Use
Fix Flox may be used in properly prepared freshwater or marine treatment tanks. Bird use must occur only under avian veterinary supervision.
Ideal for Hospital Tanks and Quarantine
A separate treatment tank helps protect healthy tank mates, sensitive invertebrates, and the main aquarium's established biological filtration.
Usage Guidelines & Instructions
Always follow the directions printed on the current bottle. The steps below describe the usual aquarium-water method for ornamental fish.
Set Up a Separate Treatment Area
Move affected fish to a dedicated hospital or quarantine tank whenever possible.
A separate system makes treatment and observation easier and protects healthy tank mates and the main aquarium's biological filter.
Prepare and Add the Treatment
Open the capsule and dissolve the powder in a clean cup of aquarium water.
Distribute the prepared mixture evenly throughout the treatment tank.
Use one 500 mg capsule per 10 gallons or approximately 38 litres of treatment water.
Repeat and Maintain Water Quality
Repeat the treatment every 24 hours.
Perform a partial water change between treatments to keep ammonia and nitrite low.
Maintain stable temperature and strong aeration throughout the treatment period.
Continue once daily for 5 to 10 days according to the current label.
Use in Pet Birds Under Veterinary Guidance
Administer Fix Flox to non-food pet birds only under the direction of an avian veterinarian.
Do not use aquarium-water calculations to determine a bird's amount.
The veterinarian must establish the appropriate amount according to the bird's species, weight, condition, frequency, and treatment duration.
Complete the Full Treatment
Complete the recommended treatment period even when the fish begin to improve, unless a veterinarian advises otherwise.
Stopping too early may allow the bacterial problem to return.
If no improvement is seen after five days, discontinue treatment as directed on the label and consult an aquatic professional.
Fix Flox Amounts by Aquarium Size
| Tank volume | Ciprofloxacin per use | 500 mg capsules |
|---|---|---|
| 10 gallons (38 L) | 500 mg | 1 capsule |
| 20 gallons (76 L) | 1,000 mg | 2 capsules |
| 30 gallons (114 L) | 1,500 mg | 3 capsules |
| 40 gallons (151 L) | 2,000 mg | 4 capsules |
| 55 gallons (208 L) | Approximately 2,750 mg | 5 to 6 capsules |
What to Expect During Treatment
Days 1 to 2
Fish may hide or eat less, and the treatment water may look slightly cloudy. Maintain the treatment schedule and keep aeration strong.
Days 3 to 5
Look for sores and red patches that stop spreading, returning appetite, improved activity, and steadier breathing.
Days 5 to 10
Complete the recommended treatment period. Afterward, perform a partial water change and restore activated carbon if normally used.
What You Need for Treatment
Prepare these supplies before administering the first treatment:
- A separate hospital or quarantine tank
- A suitable aquarium heater
- An air stone or established sponge filter
- An ammonia and nitrite test kit
- A suitable water conditioner or dechlorinator
- A small net for gentle fish transfer
- A clean cup for mixing the capsule contents
Pro Tip: Quarantine affected fish away from healthy tank mates. A small hospital tank with stable heat, strong aeration, and no substrate makes treatment and water changes easier. Remove activated carbon and switch off UV sterilization during treatment because both may reduce treatment availability in the water.
How Fix Flox Works
Each Fix Flox capsule contains 500 mg of ciprofloxacin.
Ciprofloxacin works by slowing or stopping the growth of certain susceptible bacteria when used as directed in treatment water for ornamental aquarium fish.
This may give affected fish a better opportunity to recover when the underlying condition is bacterial and susceptible to ciprofloxacin.
For non-food pet birds, ciprofloxacin should only be used under the direct guidance of an avian veterinarian.
The remainder of each capsule consists of the capsule shell and standard inactive ingredients that help keep the contents stable during storage and allow the powder to disperse when mixed with aquarium water.
Safety and Tank Notes
When used as directed, Fix Flox usually causes no problems in ornamental aquarium fish and non-food pet birds.
Incorrect amounts, unnecessarily prolonged use, or repeated antibacterial treatment may increase the risk of side effects and bacterial resistance.
Fish
Some fish may temporarily hide, eat less, appear mildly lethargic, or produce slightly cloudy treatment water.
If severe distress appears, including rapid gill movement, loss of balance, surface gasping, or remaining on the bottom, stop treatment, improve aeration, perform an appropriate water change, and seek aquatic veterinary advice.
Birds
Administer Fix Flox to birds only under avian veterinary direction.
Possible reactions may include reduced appetite, lethargy, or loose or changed droppings, especially when the amount is inappropriate or the bird is sensitive.
If the bird becomes fluffed up, inactive, has difficulty breathing, or stops eating, discontinue use and contact an avian veterinarian.
Invertebrates
Do not use Fix Flox in display tanks containing shrimp, snails, corals, or other sensitive invertebrates whenever a separate hospital tank is available.
Strong antibacterial treatment may harm sensitive species or disrupt the aquarium ecosystem.
Safe Use in Your System
Treat fish in a hospital or quarantine tank whenever possible.
Remove activated carbon and switch off UV sterilization during treatment.
Monitor ammonia, nitrite, temperature, and oxygen levels closely.
Do not combine Fix Flox with other treatments unless specifically advised by a qualified veterinarian.
Important Safety Warning
Fix Flox is intended for ornamental aquarium fish and non-food pet birds only. It is not intended for animals raised for food.
Store the capsules in their original container in a cool, dry location protected from direct sunlight, excessive heat, and moisture.
Keep the container tightly closed and out of reach of children and animals.
Always follow the directions printed on the current product label.
Shipping & Returns
Shipping Policy
Orders ship from our United States warehouse within one business day through USPS or UPS.
Qualifying orders placed before 1:30 p.m. CT, Monday through Friday, may ship the same business day.
Shipping rates and estimated delivery times are calculated at checkout.
Review Shipping Policy →Refund Policy
If there is an issue with your order, eligible products may be returned or exchanged within 30 days according to the current store guidelines.
Review the complete refund policy before returning any product.
Review Refund Policy →Frequently Asked Questions
What is Fix Flox used for in fish and birds?
Fix Flox contains ciprofloxacin and is used for certain suspected bacterial problems in ornamental aquarium fish, including persistent fin rot, columnaris-type patches, ulcer-like sores, red streaking, septicemia, and bacterial dropsy-like swelling.
Use in non-food pet birds should occur only under avian veterinary guidance.
What is the difference between Fish Flox and Fix Flox?
Fix Flox is the current Aqua Soma Labs replacement for discontinued Thomas Labs Fish Flox products. It provides the familiar 500 mg ciprofloxacin capsule strength with updated packaging and labeling.
Is Fix Flox a replacement for Aqua Cipro?
Fix Flox is presented as the updated Aqua Soma Labs ciprofloxacin product replacing older Aqua Cipro and Aqua-Cipro 500 mg products.
Is Fix Flox the same as Fish Flox Forte?
Fix Flox contains the same familiar 500 mg ciprofloxacin capsule strength associated with Fish Flox Forte.
What is inside Fix Flox?
Each Fix Flox capsule contains 500 mg of ciprofloxacin together with standard inactive ingredients and the capsule shell.
Is fish cipro the same as Fix Flox?
Fish cipro is a common search term for ciprofloxacin capsules labeled for ornamental aquarium fish. Fix Flox supplies ciprofloxacin in a 500 mg capsule.
Where can I buy ciprofloxacin for fish online?
Fix Flox 500 mg capsules can be ordered through this online store in 30-count or 60-count bottles and shipped according to the current store shipping policy.
How do I know if my fish might need ciprofloxacin?
Possible bacterial signs include persistent fin deterioration, ulcer-like sores, red patches, open wounds, columnaris-type areas, swelling, appetite loss, or rapid decline in activity.
Similar signs may result from poor water quality, parasites, fungal conditions, injury, or other causes. Seek professional assessment when the diagnosis is uncertain.
What size aquarium can one Fix Flox capsule treat?
The supplied aquarium guideline uses one 500 mg capsule per 10 gallons or approximately 38 litres of treatment water.
Can I use Fix Flox in my main community or reef tank?
A separate hospital or quarantine tank is strongly preferred. This protects healthy fish, invertebrates, corals, and the main aquarium's established biological filtration.
Does Fix Flox work in saltwater aquariums?
Fix Flox is presented for properly prepared freshwater and saltwater treatment tanks. A separate hospital system is especially important for marine aquariums containing corals or invertebrates.
How long should I treat with Fix Flox?
The supplied directions describe treatment every 24 hours for 5 to 10 days, with partial water changes between treatments.
Discontinue treatment and seek professional advice if no improvement is seen after five days.
How soon should I see improvement?
Improvement may become visible within three to five days through sores that stop spreading, returning appetite, steadier breathing, and increased activity.
Stop treatment and seek professional advice if the animal worsens or no improvement appears by day five.
Is Fix Flox safe for pet birds?
Fix Flox may be considered for non-food pet birds only under direct avian veterinary guidance. The veterinarian must determine the amount, administration method, frequency, and duration.
What bacteria does ciprofloxacin target in fish?
Ciprofloxacin is generally associated with activity against many Gram-negative bacteria and certain Gram-positive organisms. Aquarium concerns may involve susceptible Aeromonas, Pseudomonas, Vibrio, or Flavobacterium species.
Will Fix Flox harm beneficial aquarium bacteria?
Antibacterial treatment may disrupt beneficial biological filtration. Use a separate hospital tank whenever possible and monitor ammonia and nitrite closely.
Should I remove carbon or turn off UV during treatment?
Remove activated carbon and switch off UV sterilization during treatment because these systems may reduce the amount of treatment available in the water.
Can I combine Fix Flox with other fish treatments?
Do not combine Fix Flox with other antibacterial or aquarium treatments unless a qualified veterinarian specifically recommends the combination.
Can Fix Flox treat fungal, viral, or parasitic infections?
Fix Flox is an antibacterial product. It should not be expected to treat fungal, viral, or parasitic conditions unless a professional has identified a separate appropriate reason for its use.
How should I store and dispose of Fix Flox capsules?
Store capsules tightly closed in their original container in a cool, dry location protected from direct sunlight, excessive heat, and moisture.
Follow the current product label and applicable local requirements when disposing of unused capsules, treatment water, or filter media. Avoid releasing concentrated treatment into natural waterways.
More Fish & Bird Treatments
Fix Mox (Amoxicillin) 250/500 mg
A treatment for fin rot, dropsy, ulcers, and other bacterial concerns in ornamental fish. Available in 30-count and 100-count capsules.
Shop Fix Mox Amoxicillin →Fix Zole (Metronidazole) 250/500 mg
Targets certain anaerobic organisms and protozoa associated with Hexamita and hole-in-the-head concerns. Available in 60-count bottles.
Shop Fix Zole Metronidazole →Fix Doxy (Doxycycline) 100 mg
A treatment for columnaris, respiratory concerns, and Mycoplasma-related problems in ornamental fish and non-food pet birds.
Shop Fix Doxy Doxycycline →Fix Zithro (Azithromycin) 250 mg
A treatment for fin rot, columnaris, gill disease, and veterinarian-directed avian respiratory concerns.
Shop Fix Zithro Azithromycin →Fix Cin (Clindamycin) 150 mg
A treatment for certain Gram-positive bacterial concerns, including skin and soft-tissue problems in ornamental fish.
Shop Fix Cin Clindamycin →Fix Sulfa (SMZ/TMP) 960 mg
A treatment used for a range of bacterial concerns affecting ornamental aquarium fish.
Shop Fix Sulfa SMZ/TMP →Fix Pen (Penicillin) 500 mg
A treatment for certain Gram-positive bacterial concerns in ornamental fish and non-food pet birds.
Shop Fix Pen Penicillin →Fix Flex (Cephalexin) 250/500 mg
A treatment for fin rot, ulcers, infected wounds, and certain bacterial skin concerns in ornamental fish and non-food pet birds.
Shop Fix Flex Cephalexin →Browse All Treatments
Explore our complete Fish & Bird Treatments Collection for additional Fix line products and related care options.
Explore the Collection →Guides and Treatment Tips
Visit the Fish & Bird Treatments Blog for practical care guides, aquarium water-care information, and treatment tips.
Visit the Blog →Transparency & Verification
How Product Information Is Verified
Who is responsible for this page: The store editorial team responsible for reviewing and maintaining product information.
Verification snapshot: This page is written from the current product label for this item and reviewed for accuracy and consistency before publishing.
How We Verify Product Information
Label-First Accuracy
Directions, treatment duration, storage information, and warnings are taken from the current product label.
Specification Validation
Key details such as the active ingredient, capsule strength, bottle counts, and manufacturer information are cross-checked against available product specifications.
Consistency Checks
Product content is reviewed for consistent strength, directions, safety information, and storage details throughout the page.
Updates
Pages are updated when product labels, packaging, bottle counts, manufacturer information, or directions change.
See something that does not match the product you received? Please contact us so the information can be reviewed and updated.
Fish amoxicillin clavulanate 875/125mg 875mg/125mg – 30 Count
Regular price $79.99 Save $-79.99Fish Amoxicillin Clavulanate 875mg/125mg, 30 count
Shop Fish Amoxicillin Clavulanate 875mg/125mg, 30 count, for ornamental aquarium fish. Convenient aquarium-use formula with clear labeled directions.
Product Description:
Fish Amoxicillin Clavulanate combines 875mg of amoxicillin with 125mg of clavulanate in a convenient 30-count package intended for ornamental aquarium fish use. This combination product provides aquarium keepers with a clearly labeled option for maintaining their fish care supplies and managing aquarium treatment needs according to the product directions.
Each package contains 30 units with a consistent 875mg/125mg strength, making it easy to identify the active ingredients, dosage strength, and quantity when organizing your aquarium medications. Fish Amoxicillin Clavulanate is intended specifically for use with ornamental fish and should always be used according to the instructions provided on the product label.
Store the product in a cool, dry location and keep it securely closed when not in use. Always review the complete label before use and follow all aquarium-use directions carefully.
Product Details:
- Amoxicillin: 875mg
- Clavulanate: 125mg
- Size: 30 count
- Intended for ornamental aquarium fish
- Clearly labeled strength and ingredients
- For aquarium use only
Erythromycin Fish Antibiotic Powder for Fin & Tail Rot – 1,000 Gallons
Regular price $89.99 Save $-89.99Erythromycin Fish Antibiotic Powder for Fin & Tail Rot – 1,000 Gallons
Erythromycin Fish Antibiotic Powder for Fin & Tail Rot – 1,000 Gallons is a concentrated erythromycin aquarium treatment intended primarily for label-listed gram-positive bacterial concerns in ornamental fish. This size provides label-directed coverage for up to 1,000 gallons when measured and applied according to the current product label.
Key Aquarium Treatment Features
- Supports label-directed care for fin rot, tail rot, mouth sores, cloudy eyes and popeye.
- Also listed for selected aquarium concerns described as molly disease, tetra disease, wasting and swollen belly.
- The label includes guidance for cyanobacteria or red-slime concerns in aquarium systems.
Label-Listed Fish Health Concerns
This product may be considered when the visible signs and the current label are consistent with concerns such as:
- Fin rot
- Tail rot
- Mouth sores
- Eye sores
- Cloudy eyes
- Protruding eyes
- Popeye
- Molly disease
- Tetra disease
- Cyanobacteria
- Red slime
- Swollen belly
- Wasting disease
- Bacterial infection
Visible symptoms do not confirm a diagnosis. Similar signs may result from poor water quality, parasites, fungus, injury, toxins or environmental stress. Correct the aquarium environment and seek qualified aquatic guidance when the cause is uncertain.
Dosage and Application Directions
- Condition the aquarium water before measuring the treatment.
- Dose 1/4 teaspoon per 20 gallons of actual aquarium water.
- Repeat after 24 hours and complete a partial water change between treatments.
- Continue the extended bath for at least 5 days and no longer than 10 days, according to the label.
- Stop and reassess if no improvement is visible within 5 days. Allow several days before introducing a different medication.
Label priority: Always compare these listing details with the instructions printed on the bottle you receive. The physical product label controls the amount, frequency, duration, compatibility and storage requirements.
Prepare the Treatment Aquarium
- Calculate dosage from the aquarium’s actual water volume, not its advertised capacity.
- Use a separate hospital or quarantine tank whenever practical.
- Test ammonia and nitrite before treatment and throughout the complete course.
- Remove activated carbon, UV or other equipment only when the current label directs you to do so.
- Maintain stable temperature and strong aeration while observing the fish closely.
Avoid combining erythromycin with other treatments unless the current labels permit it or a qualified aquatic professional specifically directs the combination.
Coverage and Product Format
The concentrated powder format is designed for accurate measuring in a controlled treatment system. This package treats up to 1,000 gallons at the label-directed rate, making the coverage easy to compare with your hospital tank, quarantine aquarium or ornamental pond treatment volume.
wepetverse.com Product Information
wepetverse.com organizes aquarium treatments by active ingredient, intended use and total gallon coverage so fish keepers can compare products without relying only on brand nicknames. Review the current label, calculate actual water volume and select treatment according to the likely cause rather than symptoms alone.
Important Safety Notice
For ornamental aquarium and ornamental pond fish only. Not for human use or consumption. Do not use on fish intended for human consumption. Keep tightly closed and protected from children, animals, moisture, excessive heat and direct light. Use only as directed and consult a qualified aquatic veterinarian or fish-health professional when the condition is severe, recurring or unclear.
Aquarium Penicillin 500mg Forte Fish Antibiotic - 100 Tablets
Regular price $79.99 Save $-79.99Aquarium Penicillin 500mg Forte is a high-strength, 100-tablet fish antibiotic for larger ornamental-fish hospital tanks and established aquarium facilities. The title is built around the relevant phrases fish penicillin 500mg, Fish Pen Forte, aquarium antibiotic for fin rot, tail rot, bacterial mouth lesions, and penicillin fish medication. Forte identifies the 500mg tablet strength; it does not mean the product should be used more aggressively or without a supported bacterial diagnosis.
Penicillin 500mg: product details
- Active ingredient: Penicillin
- Strength: 500mg per tablet
- Package: 100 Tablets
- Product category: Aquarium fish antibiotic or antimicrobial
- Intended animals: Ornamental aquarium fish only
- System context: Freshwater or saltwater use only when supported by the product label
Common aquarium searches and condition context
This product is commonly researched in connection with the following aquarium-health terms. The list describes search and selection context; it is not a diagnosis and does not mean every case will respond to this ingredient.
- advanced fin rot
- tail rot
- bacterial mouth lesions
- Flexibacter-associated infection
- susceptible gram-positive bacteria
- infected wounds
- skin damage
- larger aquarium treatment
Who benefits from the 500mg presentation
Large koi quarantine vats, multi-tank fish rooms, and higher-volume hospital systems may find 500mg tablets more convenient when the label specifically uses that unit. The 100-count bottle offers consistent stock for managed operations. For a small tank, however, a 250mg tablet may be easier to measure. Choose by labeled plan and actual water volume, not by price per milligram or the assumption that higher strength is universally superior.
Reading fin damage correctly
Fin rot keywords attract customers with fraying, blackened or pale edges, red inflammation, and loss of tissue. Mechanical tears usually have a clear injury history and may stabilize in clean water; active bacterial erosion continues, often with inflammation or opacity. Tail biting, aggressive tank mates, ammonia burns, and poor nutrition can all imitate or initiate disease. Correct those factors before expecting tissue to regenerate.
Bacterial mouth disease versus fungus
Cotton-like plaques around the mouth are often called mouth fungus online, yet columnaris and related bacterial conditions are common possibilities. True fungus may colonize already damaged tissue. A rapidly progressing mouth or gill lesion is urgent because feeding and respiration can fail. Penicillin appears in Flexibacter and fin-rot searches, but the correct antimicrobial choice depends on the actual organism and susceptibility.
Safe inventory and course management
Store the 500mg tablets in the original, closed bottle under the labeled conditions. Record opening date, expiration, and lot number. Do not mix loose 250mg and 500mg tablets. During aquarium care, document water volume, parameter readings, start and stop dates, water changes, and response. If a course is interrupted by a water emergency, seek guidance rather than compensating with an unplanned extra amount.
When a stronger tablet is not the answer
Repeated fin loss or ulceration after antibiotics suggests an incorrect diagnosis, resistant bacteria, persistent environmental stress, parasites, or poor treatment delivery. A culture and sensitivity test can replace guesswork with evidence. Strong stewardship is part of professional aquarium care: use the narrowest appropriate product, follow the complete label-directed course, and never use ornamental-fish medication for humans or food fish.
Frequently asked questions
What does Forte mean on this product?
It means each tablet contains 500mg penicillin, compared with 250mg in the lower-strength listing.
Is this suitable for every case of fin rot?
No. Fin damage has bacterial and nonbacterial causes, and susceptibility varies. Water testing and diagnosis come first.
Essential safety information
For ornamental aquarium fish only. Not for human use, not for veterinary use in mammals, and not for fish intended for human consumption. Keep out of reach of children and household pets. Use only according to the original product label and applicable law. Do not begin treatment solely from a search result. Confirm water quality and seek an aquatic veterinarian or qualified fish-health professional for severe, uncertain, recurrent, or rapidly progressing disease.
Aquarium Minocycline 100mg Fish Antibiotic for Popeye - 30 Capsules
Regular price $79.99 Save $-79.99Aquarium Minocycline 100mg is a second-generation tetracycline fish antibiotic supplied in 30 capsules. Its strongest organic search themes are fish minocycline, Fish Min 100mg, aquarium antibiotic for popeye, bacterial dropsy, fin and tail rot, ulcers, septicemia, and bacterial care in hard-water or marine systems. The page differentiates minocycline from doxycycline by emphasizing its own formulation, search intent, and role in mineral-rich aquarium environments.
Minocycline 100mg: product details
- Active ingredient: Minocycline
- Strength: 100mg per capsule
- Package: 30 Capsules
- Product category: Aquarium fish antibiotic or antimicrobial
- Intended animals: Ornamental aquarium fish only
- System context: Freshwater or saltwater use only when supported by the product label
Common aquarium searches and condition context
This product is commonly researched in connection with the following aquarium-health terms. The list describes search and selection context; it is not a diagnosis and does not mean every case will respond to this ingredient.
- popeye
- dropsy
- fin rot
- tail rot
- bacterial ulcers
- septicemia
- gill disease
- internal bacterial infection
- hard-water bacterial treatment
Why minocycline is associated with hard water
Calcium and magnesium can affect older tetracycline-family drugs in aquarium water. Minocycline is frequently discussed as a more stable tetracycline option for hard freshwater and saltwater environments. That reputation explains high-intent phrases such as hard-water fish antibiotic and marine aquarium minocycline. Water chemistry still matters, and the exact product label should guide use; do not assume every tetracycline behaves identically in every system.
Popeye and dropsy are symptoms, not diagnoses
A protruding eye can result from trauma, gas supersaturation, water-quality damage, or bacterial infection. Dropsy describes fluid accumulation and raised scales, which may follow bacterial disease, kidney failure, chronic stress, or other internal damage. Minocycline is commonly searched when bacteria are suspected, but neither symptom automatically proves susceptibility. Early assessment offers a better chance than waiting for advanced systemic failure.
Other bacterial patterns linked to Fish Min
Search results also connect minocycline with fin rot, tail rot, gill disease, ulcers, red veins, septicemia, and internal infection. As a tetracycline-class drug, it inhibits bacterial protein synthesis. It is not a fungal treatment, and it does not resolve parasite infestation or environmental poisoning. A fish with both an ulcer and cottony growth may have primary bacterial damage with secondary fungus, requiring careful differentiation.
A compact 30-capsule specialty format
Each capsule contains 100mg minocycline, and the bottle includes 30 capsules. This makes it a focused specialty product rather than a bulk 100-count listing. Keep a written inventory, preserve the original label, and store as directed. If directions call for capsule contents to be prepared, do so exactly; do not substitute a tablet method or another tetracycline’s instructions.
Monitor systemic signs closely
Popeye, dropsy, and septicemia-like redness can indicate internal disease. Track swelling, scale position, eye size, appetite, feces, respiration, and balance as well as external lesions. Maintain pristine, stable water and low stress. Severe abdominal swelling, bilateral popeye, loss of equilibrium, or refusal to eat deserves aquatic veterinary attention because organ damage may continue even when surface signs change.
Frequently asked questions
Why might minocycline be considered in hard water?
It is often selected within the tetracycline class for better practical suitability in mineral-rich or marine systems, subject to the product label.
Does minocycline cure all popeye or dropsy?
No. Both are syndromes with bacterial and nonbacterial causes. Diagnosis and water-quality correction are essential.
Essential safety information
For ornamental aquarium fish only. Not for human use, not for veterinary use in mammals, and not for fish intended for human consumption. Keep out of reach of children and household pets. Use only according to the original product label and applicable law. Do not begin treatment solely from a search result. Confirm water quality and seek an aquatic veterinarian or qualified fish-health professional for severe, uncertain, recurrent, or rapidly progressing disease.
Aquarium Levofloxacin 500mg Advanced Fish Antibiotic - 30 Tablets
Regular price $49.99 Save $-49.99Aquarium Levofloxacin 500mg is an advanced fluoroquinolone fish antibiotic in a 30-tablet package for serious, susceptible bacterial conditions in ornamental aquariums. It aligns with searches for fish levofloxacin, levofloxacin for fish, aquarium antibiotic for systemic infection, bacterial body ulcers, fin rot, gill disease, and eye-related bacterial signs. Because this is a high-strength, specialized option, the page emphasizes diagnosis and escalation rather than presenting it as a routine first response to any sick fish.
Levofloxacin 500mg: product details
- Active ingredient: Levofloxacin
- Strength: 500mg per tablet
- Package: 30 Tablets
- Product category: Aquarium fish antibiotic or antimicrobial
- Intended animals: Ornamental aquarium fish only
- System context: Freshwater or saltwater use only when supported by the product label
Common aquarium searches and condition context
This product is commonly researched in connection with the following aquarium-health terms. The list describes search and selection context; it is not a diagnosis and does not mean every case will respond to this ingredient.
- complex bacterial infection
- systemic infection
- body ulcers
- fin rot
- gill disease
- eye infection signs
- red streaking
- gram-negative bacteria
- gram-positive bacteria
Where levofloxacin fits among fish antibiotics
Levofloxacin is a fluoroquinolone related to, but distinct from, ciprofloxacin. It is discussed for complex gram-negative and gram-positive bacterial infections, particularly when ulceration, systemic decline, or eye involvement suggests a deeper problem. An advanced-class label does not guarantee activity against the organism in a particular tank. Prior antibiotic exposure and regional resistance patterns can change susceptibility.
Symptoms that demand a full differential diagnosis
Deep sores, red streaks, swelling, bulging eyes, rapid breathing, clamped fins, and loss of balance can accompany bacterial disease. They can also reflect ammonia or nitrite poisoning, injury, parasites, osmotic stress, organ failure, or mixed infection. Test the environment and review recent changes before treatment. If multiple fish decline simultaneously, first suspect a shared water or oxygen problem.
The meaning of 500mg in a compact bottle
Each of the 30 tablets contains 500mg levofloxacin. The high-strength format requires careful verification of net water volume and the exact package instructions. Do not apply a ciprofloxacin plan to levofloxacin merely because both are fluoroquinolones. Keep the product in its original container, record the lot and expiration, and prevent access by children and pets.
A disciplined hospital-tank protocol
Use a simple, well-aerated quarantine system with stable parameters and dedicated equipment. Establish baseline photos and record respiration, appetite, swimming, lesion size, and water chemistry. Follow label guidance for filtration, water changes, and course length. Avoid simultaneous, unplanned antibiotics or antiseptics; combinations can increase stress and make the response impossible to interpret.
Professional diagnosis is especially valuable here
Levofloxacin should not become the automatic answer after another product fails. Failure may mean the disease is not bacterial, the route was unsuitable, the water remained unstable, the organism is resistant, or tissue damage is too advanced. Culture and sensitivity testing can identify whether a fluoroquinolone is justified. That evidence supports both better fish outcomes and responsible antimicrobial stewardship.
Frequently asked questions
Is levofloxacin identical to ciprofloxacin?
No. They share a drug class but are different active ingredients and must follow their own product directions.
Should it be used as a preventive quarantine medication?
No. Observation, biosecurity, and diagnosis are preferred; reserve antibiotics for supported bacterial disease.
Essential safety information
For ornamental aquarium fish only. Not for human use, not for veterinary use in mammals, and not for fish intended for human consumption. Keep out of reach of children and household pets. Use only according to the original product label and applicable law. Do not begin treatment solely from a search result. Confirm water quality and seek an aquatic veterinarian or qualified fish-health professional for severe, uncertain, recurrent, or rapidly progressing disease.
Aquarium Metronidazole 500mg Forte for Fish Protozoa - 100 Tablets
Regular price $89.95 Save $-89.95Aquarium Metronidazole 500mg Forte is the high-strength, 100-tablet choice for established fish rooms and larger ornamental-fish treatment systems. It is optimized for the genuine search cluster Fish Zole Forte, fish metronidazole 500mg, aquarium medication for Hexamita and Spironucleus, internal protozoan infection, and susceptible anaerobic bacterial disease. The Forte tablet reduces unit count where a 500mg strength is specifically called for, but it does not change the need to diagnose intestinal symptoms and calculate actual treatment volume accurately.
Metronidazole 500mg: product details
- Active ingredient: Metronidazole
- Strength: 500mg per tablet
- Package: 100 Tablets
- Product category: Aquarium fish antibiotic or antimicrobial
- Intended animals: Ornamental aquarium fish only
- System context: Freshwater or saltwater use only when supported by the product label
Common aquarium searches and condition context
This product is commonly researched in connection with the following aquarium-health terms. The list describes search and selection context; it is not a diagnosis and does not mean every case will respond to this ingredient.
- advanced Hexamita signs
- Spironucleus
- internal protozoan infection
- loss of appetite
- white stringy feces
- anaerobic bacteria
- cichlid disease
- discus disease
Forte versus 250mg metronidazole
The active ingredient is the same; the difference is 500mg rather than 250mg per tablet. Larger units can be convenient in higher-volume systems, while 250mg tablets may provide greater flexibility in smaller quarantine tanks. Do not choose the strength based on the size of the fish alone. Product directions, route, total water volume, feeding status, and professional guidance determine the appropriate format.
Internal protozoa require more than visual guessing
Hexamita and Spironucleus are associated with appetite loss, wasting, dark color, pale stringy feces, and behavioral withdrawal, especially in discus and cichlids. Similar symptoms occur with intestinal worms, bacterial disease, starvation, social stress, and unsuitable temperature. Microscopy of feces or veterinary examination provides stronger evidence than selecting a product because one symptom matches a search result.
Anaerobic bacterial relevance
Metronidazole also has activity against susceptible anaerobic bacteria—organisms that thrive in low-oxygen environments. That does not make it a replacement for ciprofloxacin, doxycycline, amoxicillin, or other fish antibiotics used for aerobic bacterial diseases. Product pages should clearly separate antiprotozoal/anaerobic intent from generic “broad-spectrum antibiotic” language so customers can make a more accurate comparison.
Protect water quality and appetite
Sick fish may stop eating, and uneaten medicated food can quickly degrade a hospital aquarium. Remove waste, maintain oxygen, and test ammonia and nitrite. If the care plan depends on food delivery but the fish refuses food, do not improvise by adding arbitrary quantities to the water; request guidance on the correct route. Follow the label concerning preparation, filtration, water changes, duration, and post-treatment carbon.
Long-term prevention for cichlids and discus
Stable warm temperatures, excellent filtration, low chronic nitrate, varied nutrition, appropriate stocking, and quarantine of new arrivals reduce intestinal disease risk. Hole-in-the-head-type lesions should prompt a review of diet and water as well as pathogens. A fish that recovers but returns to the same stressful conditions may relapse regardless of how strong the original tablet was.
Frequently asked questions
What does Forte mean here?
It identifies 500mg metronidazole per tablet, twice the active ingredient of the 250mg format.
Can metronidazole treat worms or flukes?
It is not a universal dewormer. Confirm the parasite type and choose a product labeled for that organism.
Essential safety information
For ornamental aquarium fish only. Not for human use, not for veterinary use in mammals, and not for fish intended for human consumption. Keep out of reach of children and household pets. Use only according to the original product label and applicable law. Do not begin treatment solely from a search result. Confirm water quality and seek an aquatic veterinarian or qualified fish-health professional for severe, uncertain, recurrent, or rapidly progressing disease.
Aquarium Sulfamethoxazole Trimethoprim 960mg Fish Antibiotic - 100 Tablets
Regular price $69.99 Save $-69.99Aquarium Sulfamethoxazole/Trimethoprim 960mg is a dual-action fish antibiotic containing 800mg of sulfamethoxazole and 160mg of trimethoprim per tablet. The 100-tablet bottle is optimized for searches such as Fish Sulfa 960mg, SMZ-TMP for fish, aquarium sulfa antibiotic, and sulfamethoxazole trimethoprim fish medication. Rather than presenting 960mg as one ingredient, the title and label make the two-part formula explicit so experienced aquarists can distinguish it from single-agent sulfa products.
Sulfamethoxazole Trimethoprim 800mg/160mg: product details
- Active ingredient: Sulfamethoxazole Trimethoprim
- Strength: 800mg/160mg per tablet
- Package: 100 Tablets
- Product category: Aquarium fish antibiotic or antimicrobial
- Intended animals: Ornamental aquarium fish only
- System context: Freshwater or saltwater use only when supported by the product label
Common aquarium searches and condition context
This product is commonly researched in connection with the following aquarium-health terms. The list describes search and selection context; it is not a diagnosis and does not mean every case will respond to this ingredient.
- persistent fin rot
- mixed bacterial infection
- ulcers
- dropsy
- gill disease
- Aeromonas
- Pseudomonas
- susceptible gram-positive bacteria
- susceptible gram-negative bacteria
Two ingredients, one linked pathway
Sulfamethoxazole and trimethoprim interrupt successive steps in bacterial folate production. That sequential blockade is the defining feature of SMZ-TMP and the reason it is described as a synergistic combination. In ornamental-fish discussions, it is associated with susceptible gram-positive and gram-negative organisms, including bacteria linked with gill and skin disease. The combination does not make the product universal; fungus, viruses, parasites, and water-quality injury still require different responses.
Search intent: persistent and mixed bacterial signs
Aquarists often arrive at Fish Sulfa searches after persistent fin rot, recurring ulcers, red inflammation, swelling, gill irritation, or a mixed external and systemic presentation. These signs require more than keyword matching. Check whether the fish recently shipped, fought, spawned, experienced a temperature swing, or lived through an ammonia or oxygen event. A recurring infection commonly signals an unresolved environmental or husbandry problem rather than an insufficiently strong medicine.
Understanding the 960mg label
Each tablet totals 960mg: 800mg sulfamethoxazole plus 160mg trimethoprim. The bottle contains 100 tablets for large collections, multiple quarantine systems, or carefully managed inventory. Record both active ingredients in treatment logs, because writing only “sulfa” can create confusion later. Avoid combining it with another product that contains the same or a related sulfonamide unless a qualified professional has reviewed the entire plan.
Hospital-tank checkpoints
Use actual water volume, not nominal tank capacity. Provide vigorous aeration and stable temperature, and keep ammonia and nitrite at zero. Remove waste before it decomposes, but avoid dramatic parameter changes that add stress. Follow the package instructions concerning carbon, UV, water changes, and redosing. Because biological filtration can react unpredictably during antibiotic exposure, keep conditioned replacement water ready and test more frequently than during normal maintenance.
Know when to escalate
If ulcers deepen, breathing worsens, red streaking spreads, the fish loses equilibrium, or new fish become affected, stop relying on retail symptom comparisons. An aquatic veterinarian can distinguish bacterial disease from parasites and can identify susceptibility through culture. That is especially important after a prior antibiotic has failed, because resistance, incorrect route, inadequate exposure, or an entirely different diagnosis may be responsible.
Frequently asked questions
Does 960mg mean 960mg of sulfamethoxazole?
No. It is the combined total of 800mg sulfamethoxazole and 160mg trimethoprim.
Is Fish Sulfa a parasite treatment?
It is an antibacterial combination. Do not assume it treats Ich, velvet, flukes, or worms without product-specific evidence and professional guidance.
Essential safety information
For ornamental aquarium fish only. Not for human use, not for veterinary use in mammals, and not for fish intended for human consumption. Keep out of reach of children and household pets. Use only according to the original product label and applicable law. Do not begin treatment solely from a search result. Confirm water quality and seek an aquatic veterinarian or qualified fish-health professional for severe, uncertain, recurrent, or rapidly progressing disease.
Aquarium Doxycycline 100mg Fish Antibiotic Tablets - 100 Count
Regular price $89.95 Save $-89.95Aquarium Doxycycline 100mg Tablets are a 100-count fish antibiotic option for aquarists who prefer a clearly counted, crushable dosage form. The listing targets aquarium doxycycline tablets, fish doxycycline 100mg, Fish Doxy tablets, antibiotics for fish aquariums, and bacterial-treatment searches involving fin rot, columnaris, gill disease, mouth rot, popeye, and septicemia-like symptoms. It is deliberately distinguished from the capsule product so customers can select the formulation required by their aquarium routine.
Doxycycline 100mg: product details
- Active ingredient: Doxycycline
- Strength: 100mg per tablet
- Package: 100 Tablets
- Product category: Aquarium fish antibiotic or antimicrobial
- Intended animals: Ornamental aquarium fish only
- System context: Freshwater or saltwater use only when supported by the product label
Common aquarium searches and condition context
This product is commonly researched in connection with the following aquarium-health terms. The list describes search and selection context; it is not a diagnosis and does not mean every case will respond to this ingredient.
- advanced fin rot
- columnaris lesions
- gill infection
- mouth rot
- bacterial septicemia
- popeye
- ulcers
- marine bacterial disease
Tablet convenience for established fish rooms
Tablets simplify count checks and can be useful when a label calls for crushing or pre-dissolving a measured unit. The 100-tablet package supports larger quarantine programs and long-term preparedness. Do not confuse count convenience with dosing simplicity: tank displacement, water chemistry, route, species, and the exact label still control the plan. A tablet should never be divided by guesswork when the resulting amount cannot be measured reliably.
Symptoms that lead keepers to Fish Doxy
Fraying fins, white or grey saddle lesions, mouth erosion, inflamed gills, rapid breathing, bulging eyes, red veins, and declining appetite are frequently connected with doxycycline searches. Each sign has a differential diagnosis. For example, popeye may follow trauma or water problems; fast breathing may reflect toxins or parasites; and pale patches can be columnaris, fungus, or excess mucus. Use the symptom cluster and timeline rather than one visual feature.
Water hardness, light, and treatment planning
Tetracycline-family medications can be affected by environmental conditions, and different products have different stability and preparation requirements. Review the package instructions for light exposure, mineral content, filtration, and water changes. When water chemistry makes a product a poor fit, seek qualified guidance instead of simply increasing quantity. More medication does not correct an incompatible environment or an incorrect route.
A quarantine workflow that produces useful evidence
Before starting, record baseline photos, appetite, respiration, lesion size, water parameters, and actual treatment volume. During the course, keep temperature and oxygen stable and test ammonia and nitrite daily. Use dedicated equipment to prevent cross-contamination. At the end, compare the fish with the baseline rather than relying on a vague impression. This record becomes valuable if professional evaluation or a different treatment class is required.
Why responsible wording matters
“Fish antibiotics online” and “aquarium antibiotics for sale” are high-commercial-intent keywords, but a credible product page must also explain limits. Doxycycline does not treat all bacteria and does not treat fungus, parasites, viruses, or poor water quality. Antibiotic resistance and biofilter disruption are real concerns. Use only for ornamental fish, follow the exact label, and obtain veterinary advice for severe, recurrent, or rapidly progressing disease.
Frequently asked questions
Why offer tablets when capsules are available?
Some aquarium directions and keeper workflows favor counted, crushable tablets; others favor capsules. Choose the form specified for the intended plan.
Can this be used preventively on every new fish?
Routine preventive antibiotic use is not recommended. Quarantine, observation, stable water, and diagnostic care are better first steps.
Essential safety information
For ornamental aquarium fish only. Not for human use, not for veterinary use in mammals, and not for fish intended for human consumption. Keep out of reach of children and household pets. Use only according to the original product label and applicable law. Do not begin treatment solely from a search result. Confirm water quality and seek an aquatic veterinarian or qualified fish-health professional for severe, uncertain, recurrent, or rapidly progressing disease.