Fish Pen Forte (Penicillin) exerts a bactericidal action on gram-positive and some gram-negative bacteria. Penicillin is a broad spectrum antibiotic. It is effective against a number of pathogenic bacteria associated with ornamental fish diseases. Can use for pop-eyes, infected eyes, fin or tail rot, gill disease, columnaris disease, and skin ulcerations.

Dosage & Administration
Add one tablet (500 mg) into aquarium for each 10 gallons of water to be treated. Repeat in 24 hours. It is suggested that a partial water change be made between treatments. While duration of treatment depends on type and severity of the infection, it is recommended that extended baths in the medication continue for a minimum of 5 days & for not more than 10 days. Discontinue treatment with this medication if no improvement is noted within 5 days.