I don't know where you're from or what situation your pool is in, but I'm one of the few that intentionally keeps my CYA high. I find that with a CYA of less than 60, I typically lose 3-5 ppm chlorine daily (and more if I don't have a trichlor feeder running). I'm in a high heat, high humidity climate (Louisiana), and my pool is in full sun from dawn to dusk, so I intentionally run my CYA at the 80 ppm range. Takes more chlorine to get to my initial 5-10 operating range, but I find that I only lose about 1/2 the chlorine to sun.

The only problem with running the CYa up that high in your pool is that if it doesn't work, then you're back to draining and refilling to lower it--but you might try raising it by 10-20 and see what happens. If it doesn't work, it's not too hard to drain and refill to lose that extra 20 ppm.

Janet