Add one tablet (500mg) 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 infection, it is recommended that extended medication baths continue for a minimum of 5 days but no 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.