This is a lot of three 200 ml bottles of Rid-All's Anti-Chlorine which naturally conditions tap water instantly by neutralizing the chlorine content which is very harmful to aquarium fishes. It also removes heavy metals such as arsenic, mercury or cyanide normally found in water collected from the lakes and springs. It is economical, safe, and non-toxic to aquarium plants and fishes Active Ingredients: NA2 S2 O3 5H2 O + EDTA