Instead of my usual long, drawn out explanations, I'll ask a simple question. There's some background for this, but...
Does UV burn chlorine faster at higher levels than at lower levels? Without having done any controlled tests yet, it looks like it does. When I add bleach to my pool, I typically aim for a value between the "Target" on chem geek's chart and the "Maximum" from Jason's Pool Calculator. With my CYA of 70, that's between 8 and 10. The chlorine loss to sunlight seems to be greatest from 10 to 9, and lowest from 6 to 5 (the minimum.) Is that right? It seems logical, but has anyone actually tested it?
If so, I've probably been wasting bleach trying to make sure I never fall below the minimum. (After last year's algae problems, I don't want to deal with that again, so tend to err on the high side. I should probably just trust that if I do get an algae outbreak, it's easy enough to fix.)
Does UV burn chlorine faster at higher levels than at lower levels? Without having done any controlled tests yet, it looks like it does. When I add bleach to my pool, I typically aim for a value between the "Target" on chem geek's chart and the "Maximum" from Jason's Pool Calculator. With my CYA of 70, that's between 8 and 10. The chlorine loss to sunlight seems to be greatest from 10 to 9, and lowest from 6 to 5 (the minimum.) Is that right? It seems logical, but has anyone actually tested it?
If so, I've probably been wasting bleach trying to make sure I never fall below the minimum. (After last year's algae problems, I don't want to deal with that again, so tend to err on the high side. I should probably just trust that if I do get an algae outbreak, it's easy enough to fix.)