When I started using this site 4 years ago, as a complete newbie, I quickly learned that CYA will ONLY diminish by splash-out. And yet, I have noticed my CYA has fallen from +100 levels to below 30 levels - and I have virtually NO splash out. (I add chlorine with Liquidator.) By chance I have noticed recently that some special contributors, in answers to unrelated questions on this forum, have mentioned in passing CYA "disappearance" or "a rule of thumb that CYA gets used up at 5ppm/month"
Could the experts please put this matter to rest?
Does CYA get used up or disappear naturally by means other than taking water out of the pool or hot tub?
PS: In my part of the world, I don't find the pool maintenance people that knowledgeable, but one did say that he finds CYA levels are lower after a winter's cold.