Fish Pen Penicillin 500mg – 30 Tablets

Fish Pen (Penicillin) Tablets are a dependable remedy for bacterial infections in aquarium fish. This broad-spectrum antibiotic targets gram-positive bacteria and is highly effective for conditions like fin rot, columnaris, and gill disease.

Formulated for aquarium use, Fish Pen is easy to dose, dissolves rapidly in water, and is suitable for both freshwater and saltwater systems. Whether you’re treating minor symptoms or a widespread bacterial outbreak, Fish Pen helps restore aquatic health quickly and effectively.

Key Benefits

• Broad Spectrum of Action: Treats a wide range of gram-positive bacterial infections common in fish.
• Common Fish Infections: Effective against fin rot, mouth rot, gill disease, and skin lesions.
• Easy Application: Can be dissolved directly in tank water or added to food if advised.
• Safe for Most Fish: Relatively nontoxic when used correctly across freshwater and select marine species.
• Rapid Recovery: Stops bacterial development, reduces stress, and speeds recovery time.
• Prevents Spread: Helps contain the infection, protecting healthy fish from contamination.

Directions

• Add one 500mg tablet per 20 gallons of aquarium water.
• Repeat the dosage every 24 hours with a partial water change in between.
• Continue treatment for 5–10 days depending on infection severity.
• If no improvement after 5 days, stop treatment and consult a fish health expert.

Cautions

• For aquarium use only – not for human consumption.
• Not for fish intended for human food use.
• Remove invertebrates such as shrimp and snails before dosing.
• Monitor water quality closely, as Penicillin may affect beneficial bacteria.

Storage Instructions

• Store at 59°–86°F (15°–30°C) in a cool, dry place.
• Keep lid tightly sealed to protect tablets from moisture and light.
• Check expiration date for product freshness.

Shipping & Returns

Shipping: We offer a wide range of options including Ground, Express, and International delivery. View shipping policy.

Returns: If you need to return or exchange this product, please review our refund policy here.

FAQs – Fish Pen Penicillin 500mg 30 Tablets

What does Fish Pen treat?

Fish Pen targets gram-positive bacteria and is effective against infections such as fin rot, gill disease, and columnaris.

Can it be used in saltwater aquariums?

Yes. Fish Pen is effective in both freshwater and saltwater tanks when dosed correctly.

Will it affect the biological filter?

It can. Monitor water quality carefully and reintroduce beneficial bacteria if needed post-treatment.

Is Fish Pen safe for invertebrates?

No. Remove shrimp, snails, and crabs before starting treatment, as Penicillin may harm them.

Can Fish Pen be used for bettas and small species?

Yes, as long as proper dosing is calculated based on tank volume. Avoid overdosing small tanks.

Does it discolor aquarium water?

No. Fish Pen dissolves clearly and does not stain or cloud the water.

Is it safe for use in planted tanks?

Generally, yes. Fish Pen is not known to harm most live plants.

Can I use expired Fish Pen?

No. Always check the packaging and avoid use past the expiration date for safety and effectiveness.

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