Fish Pen

Barcode : 694485673134

SKU : AS-026-PET

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Regular price $45.95 ~~$0.00~~ Liquid error (blocks/_product-price line 31): divided by 0% OFF

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Returns: Unused, unopened items in original packaging can be returned within 30 days of delivery with prior authorization. For pet safety, opened consumables, treats, food, and fish medications cannot be returned. Return shipping is covered by the customer unless the item arrives damaged or incorrect.

Damaged or Incorrect Orders: If your order arrives damaged or incorrect, email sales@thepetperch.com within 7 days of delivery with your order number and photos. We’ll send a replacement or issue a full refund immediately at no cost to you.

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Product Details

Fix Pen (Penicillin) 250mg & 500mg Capsules

Fix Pen (Penicillin) provides targeted broad-spectrum antibacterial care formulated for ornamental marine and freshwater fish. Available in both 250 mg and 500 mg strength options, it is designed to combat common bacterial pathogens in aquarium setups, helping to halt systemic infections and localized skin lesions to protect your aquatic environment. The pull-apart capsules dissolve cleanly into aquarium water to deliver pure antibiotic action without dyes or unnecessary fillers.

Features and Benefits

Targeted Antibacterial Power: Exerts a bactericidal effect against susceptible bacterial strains affecting ornamental fish.
Flexible Strength Options: Offered in 250 mg and 500 mg capsule strengths to allow accurate dosing across various aquarium sizes.
Pure Active Ingredients: Formulated with high-grade penicillin and zero artificial additives or dyes.
Broad Aquatic Support: Effective in treating common conditions including fin rot, tail rot, infected eyes, pop-eye, and body ulcerations.

Usage Guidelines & Instructions −

1. Quarantine Setup & Water Preparation Isolate sick fish in a dedicated quarantine or hospital tank prior to dosing. Turn off UV sterilizers and remove chemical filtration media (such as activated carbon), as these pull active penicillin from the water. Perform a partial water change before the initial dose to reduce organic waste.

2. Aquarium Dosing Instructions Add the contents of one 250 mg capsule per 10 gallons (38 L) or one 500 mg capsule per 20 gallons (76 L) of aquarium water. Separate the capsule halves, pre-dissolve the powder into a small cup of tank water, and pour evenly across the water surface. Repeat the dosage every 24 hours for 5 to 10 consecutive days. Conduct a partial water change between treatments. Discontinue use and consult a veterinarian if no improvement is noted within 5 days.

3. Administration in Non-Food Avian Species Fix Pen may be administered to non-food pet birds (such as pigeons) strictly under the direct guidance, diagnosis, and prescribed dosage schedule of a licensed avian veterinarian. Follow veterinary orders exclusively regarding preparation in soft food or drinking water.

4. Water Quality Management & Post-Treatment Care Maintain strong aeration and monitor water parameters like ammonia and nitrite daily during medication. Complete the full course of therapy to prevent symptom relapse. Upon completion, perform a partial water change and reintroduce activated carbon filtration to clear residual medication from the tank.

How Fix Pen Works +

Fix Pen contains penicillin, a beta-lactam antibiotic that exerts a bactericidal effect on target microorganisms.

It works by inhibiting bacterial cell wall synthesis during active multiplication, weakening the cell structure and destroying pathogenic bacteria in the aquatic environment.

Safety and Tank Notes +

Caution: Keep out of reach of children. Fix Antibiotics are for aquarium use only. Intended for ornamental fish and/or ornamental organisms, and not intended for use with fish that are intended for human consumption.

Antibiotics can disrupt beneficial nitrifying filter bacteria. Dosing in a separate hospital or quarantine tank is strongly recommended. If treating in a display tank, monitor water parameters daily.

Storage: Keep container lid tightly closed and store in a cool, dry place at controlled room temperature of 59°–86°F (15°–30°C).

Fish Pen vs Fix Pen: What Changed? +

If you previously used legacy brands like Thomas Labs Fish Pen or Fish Pen Forte, those specific lines are discontinued or hard to find. Fix Pen from SourceMax Labs serves as a direct alternative, providing the same active ingredient strengths and capsule format for ornamental fish husbandry.

Identical Active Penicillin Fix Pen provides pharmaceutical-grade penicillin (250 mg or 500 mg per capsule), matching historical aquarist expectations.

Updated Compliant Packaging Manufactured by SourceMax Labs with clear, modern labeling featuring full dosing instructions and safety notes.

Dissolving Capsule Format Features pull-apart capsules that dissolve smoothly in water, maintaining the familiar administration process.

Fresh Factory Inventory Directly supplied from recent production batches complete with clearly printed expiration dates.

Frequently Asked Questions

Do I need a prescription to buy Fix Pen? +

No prescription is required. Fix Pen is an over-the-counter medication formulated specifically for ornamental fish and aquarium care.

What conditions does penicillin treat in aquarium fish? +

It helps treat bacterial infections including fin rot, tail rot, skin lesions, infected wounds, pop-eye, and gill disease.

Can Fix Pen be used on dogs, cats, or humans? +

No. Fix Pen is strictly labeled and sold for ornamental fish and non-food organisms. It must never be consumed by humans or administered to mammalian pets.

Will Fix Pen impact my tank's biological filter? +

Broad-spectrum antibiotics can affect beneficial nitrifying bacteria in your filter media. Dosing in a separate hospital tank is strongly recommended.

How do I mix the capsules for tank dosing? +

Pull the capsule open, empty the dry powder into a cup of warm aquarium water, stir thoroughly until dissolved, and add the mixture evenly across the water surface.

Should UV sterilizers and carbon filters be turned off? +

Yes, remove activated carbon and turn off UV sterilizers throughout the treatment duration, as they remove active medication from the water.

How long should the medication treatment last? +

Daily treatments should run for a minimum of 5 days and no more than 10 days. If no clinical improvement is seen after 5 days, discontinue treatment and consult an aquatic vet.

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Fix Pen (Penicillin) 250mg & 500mg Capsules

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Fix Pen (Penicillin) 250mg & 500mg Capsules

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