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  5. Fish Pen (Penicillin) - 250mg (30 tablets)


Fish Pen (Penicillin) - 250mg (30 tablets)

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Fish Pen is an atibiotic that exerts a bactericidal action on gram-positive and some gram-negative bacteria in fish. This fish antibiotic is useful for control of some common bacterial diseases in fish, including caused by bacteria such as fin and tail rot and Flexibacter infections.

Due to recent high demand of this product, orders may take longer to ship than normal. We are shipping orders as quickly as possible. For a faster ship time, try Fish Aid brand


Active Ingredients: (in each tablet)
Penicillin V Potassium 250 mg

Useful Information

Add 1 tablet (250 mg) into aquarium for every 10 gallons of water to be treated. Repeat in 24 hours. It is suggested that a partial water change is made between treatments. While the duration of treatment depends on type and severity of infection, it is recommended that extended medication baths continue for a minimum of 5 days but not more than 10 days, Discontinue treatment if no improvement is noted within 5 days.

WARNINGS: For aquarium and ornamental fish only. Not for human use. This product should not be given to fish intended for human consumption. Keep out of the reach of children and animals. In case of accidental overdose, contact a health professional immediately.

STORAGE: Keep container tightly closed an in a cool, dry place.

Customer Reviews

Review Summary
5 Reviews
80% (4)
20% (1)
0% (0)
0% (0)
0% (0)
100% Recommend this product (5 of 5 responses)
By Linda828
Hagerstown, MD
Great buy!
February 2, 2016
I'd just purchased this product for my dog when he'd gotten sick. Because it worked so well, I opted to go ahead and order another, so I'd have it in case he should get sick again. It was amazing; crush the pill up and place it in his dinner, and the infection clears up! I definitely will return to this site for most of my pet-care needs from now on!
By Deanna
Moriarty, NM
Great product
September 3, 2015
Wonderful results from using this product in my aquarium! Would recommend highly! For large tanks, I would try the larger dosage.
By awilson308
Jacksonville Fl.
Good Value
October 1, 2013
Worked as stated very pleased with this product
By leahanna412003
Detroit, MI
Fish Pen Worked
May 21, 2013
My Beta, Charlie...had fin rot something awful. After using Fish Pen for the very first time since I bought him 2 years ago, he made a bubble nest. To say the least I was really amazed.

He had not been eating well either, and was hiding in the corner of the tank at the bottom. He's now eating again.

So thank you for making these products available. I also have a cat, and a small dog and will be depending on Pet Meds for them as well. Very timely delivery, too.
By Cat
came quick
August 21, 2012
it was easy to find ,great price and got here in no time :) very happy

Questions and Answers

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Fish-Pen Forte (Penicillin) - 500mg (30 tablets)Fish-Pen Forte (Penicillin) - 500mg (30 tablets)Reg price: $36.00
Sale price: $26.00
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