In ground pool, ~20k gal, closed last year (was sick, long story). Opened about a week ago to a green swamp. CYA measuring zero.
Have twice added about 10lbs of cya (20lbs total) slowly via skimmer, but understand now after some reading that I may have backwashed much of that out from my sand filter.
CYA still measuring zero. Added large sock full of cya to skimmer basket last night, and this morning it's completely empty.
Meanwhile, have of course been adding tons of bleach. TC is up around 30 but FC I'm having trouble keeping above 2. Pool is no longer green, even when I vacuum or sweep, just a milky white with only about 12" of visibility.
So, clearly I need to get that FC up, but I'm wondering about the CYA and if I should even worry about CYA until I get the pool back in shape. Could all the CYA I've been adding just be "feeding" the contaminants? Should I keep trying to get CYA up WHILE I'm shocking the pool? Or is that just aggravating the problem?