Shower Filter for Eczema in Houston

My (28) gf (26) suffers from eczema and we have gone through 2 different shower filters that don’t seem to help with her constant itching post-shower, one of which was an Aqua Earth shower filter 15 stage from Amazon. When we travel to other areas of the country, particularly the Midwest, she doesn’t suffer from itching directly after a shower. The research we’ve found indicates that it could be related to higher chloramine levels found in the Houston water supply.

Has anyone with eczema or other skin conditions had success with a shower filter that doesn’t cause itching or stop working after a few weeks due to Houston’s chloramine levels?