Is a dechlorinator which rapidly removes chlorine, chloramine and heavy metals such as zinc and lead from tap water, allowing fresh tap water to be added directly to the pond. Using Koi Care Chlorgo is the ideal water care solution and avoids putting fish in any unnecessary danger from these potentially toxic substances. Chlor-Go is also a great copper remover and has a calming effect on fish being transported. It should always be used in transportation bags and isolation tanks regardless of whether or not tap water has been used. Recommendation: It is advisable to purchase a larger bottle than needed to treat your pond volume. Sometimes it is necessary that partial water changes need to take place rapidly and storing more than you need will eliminate the wait for delivery when your fish may be at risk... You won't be charged any more for delivery as our shipping rates are fixed. 250 ml treats 9000 litres (2000 gallons)