Do you know what the CYA reading was when you closed it last fall and have you checked the CYA this year? Many times over winter, you have bio-degradation of CYA into ammonia and it can take massive amounts of chlorine to get rid of it. I can't imagine that after that mega-dose that you had none this morning though. Do you have a it that can measure a CC (combined chlorine) reading?
If you don't have a good kit, you should get one. The one we recommend is the Taylor K-2006 or 2006C which you can get through the test kit link in my signature below. You're gonna need it because most kits can't read chlorine levels as high as you'll need to clean this up.
Welcome back to the Pool Forum!
Bookmarks