King British De-Chlorinator makes tap water safe for fish. Use during initial tank set-up and whenever conducting partial water changes. De-Chlorinator neutralises harmful chlorine & chloramines and detoxifies heavy metals allowing tap water to be safely added to a fish tank. Also contains Aloe Vera to aid fish health. For use in tropical & coldwater aquariums. One 100 ml bottle will treat 900 litres of tap water.