Today I was told about a pool that one of my coworkers takes care of. Every week the pool is low on salt. The pool has an automatic filler, so we have been working under the assumption that it is probably losing water, and the autofill keeps it topped off. Today the pool was low on salt again. It had dropped by about 200 ppm since last week. When the tech tested the CYA, he found that the CYA had not dropped. So how could it be possible to lose 200 ppm salt, but not see a change in the CYA?