For Situations where tap quality is poor, where excess chlorine is present as evident by the smell, or where the water authorities might use chemicals that harm fish, then Extra Power Water Purifier is recommended. Contains a trihydrate, a pentahydrate, heavy metal complexors and mould inhibitors to deal with the worst of water conditions. Extra Power Water Purifier neutralizes quantities of chlorine, neutralizes chloramine, complex heavy metals, and more. Dose Rate: A 100mL bottle treats 1000L of tap water or 1 mL per 10 litres.