Fix Mox (Fish Mox) Amoxicillin 250mg & 500mg Fish Antibiotic Capsules

Fix Mox (Fish Mox) Amoxicillin Capsules - Fish & Bird Antibiotic 250 mg / 500 mg

Fix Mox 250 mg and 500 mg is a pharmaceutical-grade, over-the-counter (OTC) amoxicillin fish antibiotic in capsule form for ornamental aquarium fish and non-food pet birds. Often searched as Fish Mox, Fish Mox Forte, Aqua Mox or FISHBIOTIC Amoxicillin, Fix Mox from Aqua Soma Labs is the modern replacement for discontinued Thomas Labs Fish Mox. It helps manage common bacterial problems such as dropsy (body swelling), fin and tail rot, columnaris, bacterial hemorrhagic septicemia, red streaks, gill disease, swim bladder infections, abscesses, and skin ulcers in both freshwater and saltwater aquariums. Under the guidance of an avian veterinarian, the same capsules may also be used as part of an amoxicillin treatment plan for selected bacterial issues, including crop infections and salmonella/paratyphoid, in pigeons and other pet birds.

Fix Mox supplies 250 mg or 500 mg amoxicillin per capsule, giving hobbyists flexible options whether they are treating a small hospital tank, a larger community aquarium or, with veterinary input, a busy loft or aviary. Available to buy online with fresh expiration dates and clearly labeled strengths, Fix Mox is a reliable Fish Mox replacement that ships directly from our U.S. warehouse.

Use Fix Mox to aid recovery when you notice early signs of bacterial stress in fish, such as lethargy, bulging eyes (pop-eye), red streaks, open sores, rapid breathing or unexplained body swelling.

In birds, Fix Mox should only be used when an avian veterinarian has specifically recommended amoxicillin for a suspected bacterial problem. Addressing potential infections early with appropriate amoxicillin treatment, together with good water quality, suitable housing and professional guidance when available, helps your fish and birds maintain a stable, healthy aquarium or aviary.

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 U.S. warehouse via USPS or UPS.

Important Notice: This product is intended for aquarium and ornamental fish and pet birds only. It is not for human consumption or for animals used for food. We do not sell or recommend this product for human use.

Benefits of Fix Mox for Fish & Birds

• Broad-Spectrum Support for Common Fish Infections

  Fix Mox provides broad-spectrum amoxicillin coverage for ornamental fish, helping manage bacterial issues such as dropsy (body swelling), fin and tail rot, red streaks, gill disease, swim bladder infections, and skin ulcers in both freshwater and saltwater aquariums when used as directed.

• Helps With External and Internal Bacterial Problems

  The amoxicillin in Fix Mox can be used as a fish antibiotic for external signs like frayed fins, open sores, an infected wound or red patches, as well as internal infections (like hemorrhagic septicemia) that cause swelling, pain, lethargy or loss of appetite in a hospital tank setting.

• Flexible 250 mg and 500 mg Capsule Strengths

  Each capsule supplies either 250 mg or 500 mg amoxicillin, making it easy to scale milligram dosing from smaller quarantine tanks to larger community systems. Hobbyists can follow typical guidelines of 250 mg per 10 gallons or 500 mg per 20 gallons of water, or consult an aquatic veterinarian for tailored advice.

• No Vet Prescription Required

  Fix Mox is available over the counter and can be purchased online without a veterinary prescription. Keep it on hand in your fishkeeping supplies so you are ready to act at the first signs of bacterial infection in your aquarium.

• Easy to Use for Fish and Vet-Directed Bird Treatments

  For fish, pull-apart capsule contents dissolve quickly in tank water so medication spreads evenly and reaches shy or hiding fish. Under avian veterinary guidance, capsules can also be opened and carefully mixed into soft food or drinking water for selected pet birds facing issues like crop infections.

• Ideal for Hospital Tanks and Quarantine Setups

  Fix Mox works best in a separate hospital or quarantine tank, where you can remove carbon and UV, maintain stable water quality and keep a close eye on affected fish without exposing healthy tank mates or sensitive invertebrates to unnecessary antibiotics.

• Modern Alternative to Discontinued Brands

  Many hobbyists now buy Fix Mox as their go-to replacement when older Thomas Labs Fish Mox or Aqua Mox brands are no longer available. Clearly labeled strengths and fresh stock make it easier to match the dose to your aquarium or vet-directed bird treatment plan.

Fish Mox vs Fix Mox: What Changed?

Many aquarists searching for Fish Mox, Fish Mox Forte or Aqua Mox find that these older brands have been discontinued or are difficult to source. Fix Mox from Aqua Soma Labs uses the same active ingredient (amoxicillin) at the same strengths and is designed as a direct replacement for aquarium use.

Dosage Guidelines & Instructions

Directions for Use:

1. Set Up a Separate Treatment Area

   Whenever possible, move sick fish to a dedicated hospital or quarantine tank before dosing. Remove activated carbon and turn off UV sterilizers so they do not strip the amoxicillin from the water. Perform a 20-25% partial water change before the first dose to improve water quality and reduce stress on fish.

2. Dose for Fish Aquariums

   Follow the label-style guideline of 250 mg amoxicillin per 10 gallons (38 L) of water or 500 mg amoxicillin per 20 gallons (76 L). Open the capsule, mix the powder in a small cup of aquarium water, then distribute the solution evenly around the hospital tank. Repeat the dose every 24 hours for 5-10 days, making a partial water change between treatments. If there is no improvement after about 5 days, or if fish appear worse, discontinue treatment and seek aquatic veterinary advice.

3. Use in Pet Birds (Under Veterinary Guidance)

   Fix Mox can be used in pigeons and other non-food pet birds only under the direction of an avian veterinarian. Your vet will determine the correct mg-per-kg dose, how often to give it and how long the course should last. Capsules are usually opened and mixed with soft food or drinking water so the full prescribed dose is taken, but you should follow your vet's exact instructions rather than guessing.

4. Maintain Water Quality & Complete the Course

   Throughout treatment, monitor ammonia, nitrite and temperature closely and keep aeration strong in the hospital tank. Continue Fix Mox for the full recommended course unless an aquatic or avian veterinarian advises otherwise; stopping this medicine early can allow symptoms to return. After the course, perform a partial water change and then replace activated carbon or other chemical media to remove any remaining medication and help restore water clarity and biological balance.

Pro Tip: Treat sick fish in a separate hospital tank instead of the main display whenever you can. This helps protect your display aquarium's biofilter and sensitive invertebrates while you focus treatment where it is needed most.

What Makes This Antibiotic Effective?

• Active Ingredient: Amoxicillin Trihydrate (250 mg or 500 mg per capsule)

  Fix Mox contains amoxicillin, a broad-spectrum beta-lactam antibiotic in the penicillin family. Amoxicillin works by interfering with bacterial cell wall formation, which helps stop susceptible bacteria from multiplying and supports control of common Gram-positive and some Gram-negative bacteria linked with fin and tail rot, skin ulcers, red streaks and certain gill infections in ornamental fish when used as directed.

• Inactive Ingredients

  Each capsule also contains pharmaceutical excipients that help keep the amoxicillin stable on the shelf and allow the capsule contents to disperse and dissolve properly when opened into aquarium water or mixed with soft food for birds under veterinary guidance.

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Frequently Asked Questions

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