Fish Aid Doxycycline Hyclate is an antibiotic 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 Septicemia, Mouth Rot, and Fin and Tail Rot.
Add 1 tablet (100 mg) into aquarium for every 15 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 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. To remove harmless yellow color, change 20% of water and use charcoal filter until clear.