Fish antibiotics Penicillin

Fish peni (penicillin) is a widely used antibiotic to exert a bactericidal action against gram-positive and gram-negative bacteria in fish. The fish penicillin is intended for ornamental fish only, not for human consumption.

At TheFishAntibiotics, we provide a wide range of fish antibiotics that help to keep your aquarium buddies healthy. Famous and trusted brands manufacture all our fish penicillin antibiotics. At TheFishAntibiotics, we offer;

We sell all our fish antibiotics with the latest expiration dates and an instruction manual explaining the usage and directions of medicines.


Fish antibiotics penicillin (Fish Pen and Fish Pen Forte) effectively treat columnaris disease, gill disease, pop-eyes, fin rot, and other bacteria-associated diseases in ornamental fish.


A 500mg capsule of fish penicillin can treat 20 gallons of aquarium water, while the 10mg capsule effectively dissolves in 10 gallons of water. Open the desired capsule and dissolve it in the aquarium. Repeat the process in 24 hours and change the partial water between treatments. We recommend continuing the medicated baths for a minimum of five days but not more than 10 days.

Why You Should Buy Our Fish Antibiotics Penicillin

  • All our fish penicillin antibiotics are USP graded and manufactured by famous pharmaceutical companies in the USA.
  • We offer the latest expiration dates and free shipping.
  • TheFishAntibiotics takes only 1 business day to ship your orders.
  • The wide collection of fish antibiotics makes us an ideal place to buy fish antibiotics online.


Reach out to our customer support today; place your order before 2 p.m. to avail the chance of same-day shipping.