So last night I had a few beers and the pool was a little low so I put the hose in and it filled for 6 hours. So this am I woke up and it was almost to the top but it seemed it was draining somewhere like a safety drain. Are there safety drains that keep pools from overflowing or was I just lucky. Maybe I added 5000 gallons. I shocked it this morning but it was still clear. How much will I have lowered CYA. I will just use pucks I guess to bring it back up. This should teach me a lesson!