King British Methylene Blue No 10

King British Methylene Blue is a longstanding treatment for aquaria, used by generations of fish keepers. It is effective against a range of fungal & bacterial infections. For use in coldwater & tropical aquariums. One 100ml bottle will treat up to 900 litres of tank water. Active Ingredient: Contains: Methylene Blue 2.44% w/w. Available in a 100ml bottle.