This is not the case with chloramines, so steps should be taken to remove chloramines. Most pet stores have sold de-chlorinating agents for years and generally have recommended using them. These chemicals used to remove chlorine should work just as well for chloramines. Several manufacturers have been adding chloramine information on their product labels for years. Ammonia is also released when chloramines are chemically removed.
Ammonia can be harmful to fish, even though fish produce some ammonia as a natural byproduct.
Although ammonia levels may be tolerable in individual tanks or ponds, commercial products are available to remove excess ammonia. Also, biological filters, natural zeolites, and pH control methods are useful in reducing the toxic effects of ammonia. Yes, chloramines affect saltwater fish just as they affect freshwater fish. Chloramines will need to be removed if the water used to make saltwater solutions comes from a chloraminated supply. Yes, Koi are just as susceptible to being harmed by chloramines as any other fish.