Seachem SafeSeachem Safe removes chlorine, chloramine and ammonia. It converts ammonia into a safe, non toxic form that is readily removed by the tanks biofilter. It may be used during tank cycling to alleviate ammonia nitrite toxicity. It detoxifies nitrite and nitrate, allowing the biofilter to more efficiently remove them. It is non acidic and will not impact pH. It will not overactivate skimmers. Note: Use at start up and whenever adding or replacing water.