Chloramines, what are they?

Chloramines are a disinfectant used to kill harmful bacteria in some municipal water systems.  It’s made up with a combination of chlorine and ammonia.  Together; these two chemicals are very toxic to fish.  Some city water systems add chloramines to their water because it will last much longer in the pipes than just chlorine alone.  Chloramines are so toxic to fish, that it passes directly through the gills and into the blood stream causing death in minutes.  Chloramines take much longer to dissipate from the water then just chlorine alone.  The old rule of thumb was to let the water stand for about 24 hours so the chlorine would dissipate out of the water, or to add an air stone to circulate the water so you could use it even sooner.  If your water contains chloramines, you must use a chloramine remover when doing water changes, or adding any water to an aquarium that has fish.  You can contact your local water company to find out if they add chloramines or are ever planning to.

Even if chloramines aren’t added now, you still can’t be 100% sure they never will.  I have contacted my city water in Detroit, and have found they don’t add chloramines now and aren’t ever planning to in the future. But that still doesn't guarantee that some day they start to. I contact our city water, at least once a year just to make sure that they haven't started to or are ever planning to add chloramines. I also keep a bottle of chloramine remover on hand for any unseen emergencies that would evolve chloramine.

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