These chemicals must be neutralized with a water treatment that removes chlorine and chloramine . Water with chlorine and chloramine in it must be treated with a product that will neutralize both chemicals. When fish are moved from aquarium to aquarium, or they are in a weakened condition from transporting, their stress is increased and their protective slime coating may be lost. It is critical however, to maintain a stable pH level in your tank. There are kits available to test the pH level.
Products are available to bring the pH up or down as needed.
Home test kits with pH adjusters are also available. Ammonia Ammonia poisoning, the leading cause of fish loss, is most likely to occur at toxic levels in a newly established tank where the process of biological filtration has not been established, in an old aquarium where the pH has become alkaline, or in an over-crowded tank. Ammonia, which destroys the mucus membranes of fish, is secreted by fish directly through the gills as a waste product, and by the bacterial breakdown of fish waste, uneaten food and plant by-products. This causes the ammonia levels in the tank to reach toxic levels, known as ammonia poisoning. Adequate and proper filtration, and regular water testing , help keep toxic ammonia levels from occurring.