Fish Pen (Penicillin) 500mg – 30 Tablets

Fast-Acting Fish Antibiotic for Bacterial Infections

Fish Pen Tablets are a trusted, broad-spectrum fish antibiotic used to treat gram-positive bacterial infections in ornamental fish. Whether you're managing gill disease, fin rot, or skin lesions, this powerful formula supports faster healing and restores health in both freshwater and saltwater aquariums.

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Benefits of Fish Pen (Penicillin) Tablets

• Broad-Spectrum Protection: Targets gram-positive bacteria causing common fish illnesses.
• Treats Multiple Conditions: Effective against gill disease, mouth fungus, body ulcers, and fin damage.
• Easy-to-Dose Tablets: Dissolves rapidly in tank water or can be administered through food under guidance.
• Safe & Effective: Minimal toxicity for most species when dosed properly.
• Rapid Recovery Support: Stops bacterial growth, limits spread, and helps fish regain appetite and normal activity.

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Directions for Use

• Add one 500mg tablet for every 20 gallons of aquarium water.
• Repeat every 24 hours, performing a 25% water change between doses.
• Treatment should continue for 5–10 days depending on the condition.
• If there’s no improvement within 5 days, stop use and consult a fish care professional.

Cautions & Warnings

• For ornamental aquarium use only – not for human or food fish.
• Remove invertebrates like shrimp and snails before treatment to prevent harm.
• Penicillin may temporarily affect biological filtration – monitor water parameters during treatment.

Storage Instructions

• Store in a cool, dry place at 59°–86°F (15°–30°C).
• Keep the container tightly sealed and protect from moisture or direct light.
• Check expiration date before use for best results.

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FAQs – Fish Pen (Penicillin) 500mg Tablets

• What does Fish Pen treat?
  It treats gram-positive infections like fin rot, body ulcers, gill inflammation, and mouth rot.
• Can it be used in saltwater tanks?
  Yes. Fish Pen works in both freshwater and saltwater systems.
• Does it affect the tank’s biofilter?
  It may reduce beneficial bacteria. Monitor closely and use a stabilizer if needed after treatment.
• Is it safe for shrimp and snails?
  No. Remove all invertebrates before treatment.
• Is Fish Pen safe for small tanks?
  Yes, just ensure accurate dosing. Overdosing in small tanks can be harmful.
• Will it change water color?
  No. Fish Pen dissolves clearly and does not cloud or discolor water.
• Can I use it in planted tanks?
  Generally safe for most aquatic plants, but always test in a separate tank if unsure.
• Can I use expired Fish Pen?
  No. Discard expired tablets and use only fresh product for effective treatment.
• Where can I buy Penicillin for fish?
  Order directly from our secure online store at DogsAntibiotics.com.

Buy fish antibiotics online without a vet prescription at DogsAntibiotics.com — trusted by aquarium keepers for safe, effective, and fast-acting fish medication delivered across the USA.