Only about a month and a half ago, I had a CYA level of about 50, but now is significantly less than 30 (I can still clearly see the dot after filling the tube when testing using the Taylor K-2006). I backwashed a few times during that time and did not experience much splash-out or carry-out. I do not add CYA regularly as I use bleach for chlorination. I'm left to ponder what the chances are of the CYA degrading on its own in that amount of time. So how long does it usually take for CYA to disappear naturally?