Prime? is the complete and concentrated conditioner for both fresh and saltwater. Prime? removes chlorine, chloramine and detoxifies ammonia. Prime? converts ammonia into a safe, non-toxic form that is readily removed by the tank?s 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. It will also detoxify any heavy metals found in the tap water at typical concentration levels. Prime? is non-acidic and will not impact pH. Prime? will not overactivate skimmers. Use at start-up and whenever adding or replacing water.