Removing Chloramines for Fish Tanks


Information for Pet Stores and Fish Aquarium Owners

While chloramines are safe for most pets, they must be removed from tap water used for aquatic life in aquariums and ponds.

What does this mean for aquarium and pond owners?

Chloraminated water is superior to state and federal drinking water standards, but chloramines are harmful to fish when they directly enter the bloodstream. Since fish and other aquatic animals take chloramines directly from the water into their bloodstreams through their gills, chloramines, like chlorine, must be removed from water used for keeping live fish and other aquatic life.

What types of aquatic life do chloramines affect?

Chloramines, like chlorine, will kill both salt and fresh water fish and other aquatic life including Koi fish, lobster, shrimp, frogs, turtles, snails, clams and live coral. Chloramines, therefore, like chlorine, must be removed before using tap water in your fresh or salt-water aquarium or pond.

How can I remove chloramines from my water?

A water-conditioning agent or an activated carbon filter specifically designed to remove chloramines must be used according to product instructions. If you are already using one of these products to remove chlorine, it’s possible that the same product will also remove chloramines. However, you must read the product label to be sure. Your pet supplier should be able to provide any further guidance you may need.

Are both saltwater fish and fresh water fish affected by chloramines?

Yes. Chloramines affect saltwater fish just as they affect freshwater fish. Chloramines must be removed if the water used to make saltwater solutions comes from a chloraminated supply.

Won’t letting water sit for a few days remove chloramines from tanks or pond water?

No. Unlike chlorine, which dissipates when water sits for a few days, chloramines are longer lasting and may take weeks to dissipate. This is not a safe method for removing chloramines.