It is a debatable topic but some say that chloramine can be filtered out by using activated granular charcoal. The adulterated water must have full contact (thus block filters are not advised) and stay in contact with the AGC for a certain time, not just passing thru it. Furthermore the AGC filter has a capacity and decreases as use progresses.
Another aspect is that chloramine also changes, releases, other toxins not often mentioned in water filtering literature, thus the implications of the addition of chloramine has more toxic outcomes then initially thought.
Water filter sellers are not the best way for us to find out about water filter efficacy. The best back up is for us to know about our filtering system is to test our water.
"There is often an expectation that there is a "filter" for every contaminant that specifically identifies that contaminant and, as if by magic, "takes it out." A frequent question is "How much does your filter take out?" It isn't quite as simple as that, especially with "problem contaminants" like chloramines".
"While the reverse osmosis membrane itself does not remove chloramines, every respectable RO unit is equipped with two or more high quality carbon filters. Pre-filters, the filters that process the water before the membrane, receive water at a very slow rate of flow and therefore work under excellent conditions for chloramine reduction. The use of the high quality cartridges actually should provide superb chloramine reduction".
•Filtration for chloramine is more complex compared to filtration for chlorine.
•There is NO certified showerhead filter to remove chloramine. The high flow rate and large volume of water passing through a showerhead renders the showerhead filter useless.
•Sink water filters for chloramine handle low flow, cold water conditions only.
•Even with a comprehensive filtration system, no filtration system engineer will guarantee complete removal of chloramine. Chlorine is by far easier to remove with inexpensive carbon filtration.