Fix Zole (Fish Zole) Metronidazole Tablets - Fish & Bird Antibiotic 250 mg / 500 mg

Fix Zole (Fish Zole) Metronidazole 250mg and 500mg is a metronidazole fish and bird antibiotic in tablet form. Shoppers also look for it as fish metronidazole, fishzole, or by older brand names like Fish Zole Forte, Aqua Zole, and aquazole. It is now made by Aqua Soma Labs and sold over the counter, replacing the discontinued Thomas Labs Fish Zole. If you have used MetroPlex in the past, this is a tablet-based alternative.

Hobbyists use Fix Zole to help manage internal parasites and intestinal flagellates (protozoan flagellates) such as Hexamita and Spironucleus. These can show up in several ways in susceptible freshwater fish, from feeding and behavior changes to visible physical signs (see the symptom list below). Many keepers prefer treating in a hospital tank or quarantine setup for easier observation and control.

Metronidazole is a nitroimidazole medication with activity against certain protozoa and anaerobic organisms by disrupting DNA processes in susceptible targets. When used as directed, it can be part of a broader care plan that also includes stable water quality, reduced stress, and good nutrition. It is not intended for ich or flukes, and it is not a first choice for typical fin rot unless a professional has confirmed the cause.

Fix Zole from Aqua Soma Labs delivers 250 mg or 500 mg metronidazole per tablet in 60-count bottles with fresh expiration dates. Pick the strength that matches your tank size and treatment plan, with no splitting or measuring. You can pre-dissolve a tablet in a small cup of aquarium water before adding it to a treatment tank, which helps it spread evenly.

Use Fix Zole when fish or pet birds show signs that may be linked to protozoan flagellates or anaerobic-sensitive issues. Common signs differ between species, so check the lists below to identify what to watch for.

Supporting treatment with clean water, stable temperature, 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 directly from our U.S. warehouse the same business day. No veterinary prescription required for aquarium fish use.

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.

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:

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 are often associated with appetite loss, weight loss, white stringy poop, Malawi bloat, and "hole-in-the-head" type signs in susceptible freshwater fish such as cichlids and discus.

• No Veterinary Prescription Required

  Fix Zole is available over the counter for aquarium fish use. No vet prescription or doctor's visit is needed to purchase. For pet birds, always consult an avian veterinarian before administering metronidazole.

• Avian Vet-Guided Option

  In non-food pet birds, metronidazole may be used under avian veterinary guidance for certain protozoal concerns such as giardia, frounce (common in raptors), and as an effective pigeon canker treatment for trichomonosis, especially in racing pigeons and related species.

• Flexible 250 mg or 500 mg per Tablet

  Choose the strength that fits your setup and plan. A consistent mg per tablet (in 60-count bottles) lets you scale the dose across different tank sizes or care routines.

• Ideal for Hospital Tanks and Quarantine

  Many hobbyists treat in a separate hospital tank for better observation and to help protect the display tank's biofilter and sensitive tank mates. Tablets can be pre-dissolved in a small cup of aquarium water for more even distribution.

• Fits a Complete Care Plan

  Medication alone rarely fixes the problem. The best results come when you also keep the temperature stable, the water clean, stress low, and feeding appropriate.

• Targeted, Not a One-Size-Fits-All Remedy

  Fix Zole is not typically used for ich (white spot), gill flukes, or Costia, and it is not a first choice for typical fin rot unless the cause has been confirmed. If symptoms persist, confirm the diagnosis or consult an aquatic or avian professional.

Dosage Guidelines & Instructions

Directions for Use:

1. Set Up a Separate Treatment Area

   Move affected fish to a dedicated hospital tank when possible. This helps you monitor behavior, control dosing more precisely, and reduce unnecessary exposure in the display aquarium.

2. Dose for Fish Aquariums

   You may pre-dissolve the tablet in a small cup of aquarium water, then distribute it evenly across the fish tank you are treating:
   
   250 mg: Add one 250 mg tablet per 10 gallons (38 L) of water.
   500 mg: Add one 500 mg tablet per 20 gallons (76 L) of water.
   
   Repeat the dose every 24 hours, performing a partial water change between treatments.

3. Filter Adjustments

   Remove activated carbon or other chemical filtration media during treatment and keep good aeration running, since carbon can reduce medication availability in the water.

4. Continue the Course and Monitor Results

   Continue daily treatment for 5 to 10 days (do not exceed 10 days). If there is no improvement within 5 days, discontinue treatment and consult an aquatic professional.

5. Use in Pet Birds (Under Veterinary Guidance)

   Only administer metronidazole to non-food pet birds under the direction of an avian veterinarian. Your vet should confirm the diagnosis and advise the correct mg-per-kg dose, frequency, and duration. Tablets may be given whole, split, or crushed and mixed into soft food exactly as instructed.

These figures come from the label-style guideline of 250 mg per 10 gallons, roughly 25 mg per gallon. Dose by the water volume of your treatment tank, not by the number of fish, give one dose every 24 hours for 5 to 10 days, and round to the nearest practical tablet. The bottle label or your aquatic veterinarian takes priority over this quick-reference chart.

What to Expect During Treatment

Pro Tip: After treatment, perform a partial water change and reintroduce activated carbon (if you normally use it) to help remove residual medication from the water.

How This Medication Works

• Active Ingredient: Metronidazole (250 mg or 500 mg per tablet)

  Metronidazole is a 5-nitroimidazole medication that is activated in susceptible anaerobic organisms and certain protozoa. During activation, short-lived reactive intermediates can damage DNA and disrupt cellular function in these targets. Hobbyists may also recognize metronidazole tablets under earlier names such as Thomas Labs Fish Zole, Fish Zole Forte, and Aqua-Zole, or as the "fish Flagyl" some keepers ask for, since flagyl for fish is simply the same active ingredient found in the prescription medication Flagyl.

• Inactive Ingredients

  Like most tablets, Fix Zole includes inert excipients (such as binders and stabilizers) that help the tablet hold its shape, store well, and dissolve or disperse when mixed with water. The exact excipient list is not always published and may vary by batch.

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