Two major reasons IMO: 1. Chlorine tastes nasty in water. (The correct solution IMO here is to use chloramine instead.) 2. Chlorine removal may be a side eff

Two major reasons IMO: 1. Chlorine tastes nasty in water. (The correct solution IMO here is to use chloramine instead.) 2. Chlorine removal may be a side effect. Carbon filters are used to remove all kinds of nasties and/or unpleasant tastes and odors. And they remove chlorine. Carbon-filtering without removing chlorine may be difficult or impossible. > Well, as a former competitive swimmer, if chlorine does any harm whatsoever I am a write off. Research is mixed, but the actual danger to swimmers might not be the chlorine per se. There is some (conflicting) evidence that nitrogen trichloride and/or dichloramine exposure increases asthma risk in swimmers and in people who work near indoor swimming pools. They also smell terrible — the nasty “chlorine” smell, especially around indoor pools, is dichloramine and nitrogen trichloride. Fortunately your tap water is unlikely to meaningfully expose you to these. You need a nitrogen source and excess chlorine, which should not exist at the same time in any substantial amount in tap water. A chlorinated swimming pool plus sweat and/or urine is a different story.