Seachem Prime is a complete and concentrated conditioner for both fresh and salt water. Prime removes chlorine, chloramine and ammonia. Prime converts ammonia into a safe, non-toxic form that is readily removed by the tanks biofilter. Prime may be used during tank cycling to alleviate ammonia/nitrite toxicity. Prime detoxifies nitrite and nitrate, allowing the biofilter to more efficiently remove them. Prime also promotes the production and regeneration of the natural slime coat. Prime is non-acidic and will not impact pH. Prime will not overactivate skimmers. Use at start-up and whenever adding or replacing water.