Chloramines have to be removed from water for aquariums as well as hydroponic applications. This is because (A) it kills fish, chloramine goes directly from the water through the gills into their bloodstreams, and (B) it can inhibit plant growth.
For aquarium water, a common approach is to add sodium thiosulfate or another suitable additive into the water. The average tap water requires between 0.04 and 0.12 grams of crystalline sodium thiosulfate per gallon. Products are available online and at your local pet/aquarium supply store.
What you can also do is make use of carbon filtration as explained above. You need to be careful, though: The carbon won’t reduce ammonia content. In fact, it will actually increase ammonia levels. Thus, you must add a primer that converts the chemical into a safe, non-toxic form.
The same applies to a bunch of additives. If a product label mentions chlorine and chloramine but does not list ammonia, beware. Another agent might be required complementary.