Waterlife myxazin professional is a high concentrated broad spectrum bactericide for treating fin rot, ulcers, and other bacterial infections. Myxazin may also be used as a prophylactic treatment for disease prevention in order to reduce the risk of disease when new fish are introduced. It is safe for use with fish, plants, and filtration bacteria. Available in 100ml, 250ml, and professional strength 500ml and 1 litre bottles.. This highly concentrated 500ml bottle treats up to 3,000 litres over a 5-day course.