Filter Carbon is a high quality filter carbon to be used for freshwater and saltwater aquariums. The active surface of 1000 symg/g removes detrimental matter from the water circulation such as gases chlorine dyes and organic metabolic products. Extremely low in phosphates and suitable for continuous use. For 100 litres of water at an active time of four weeks maximum: in freshwater tanks approx. 120ml of Ffilter Carbon; in saltwater tanks approx. 250ml of Filter Carbon.