After a few weeks learning the ropes I think I understand the need to keep a high FC to get rid of algae.
I was pleased with an otherwise sparkling pool (new home owner, old pool) and very low chlorine making it quite comfortable. But I noticed algae growing as the chlorine was getting used up quickly. We have been at 85-90 degrees for weeks.
Using TFP, concentrated CLorox bleach (thanks Costco) and sweeping and brushing I've now managed to go from 20 CYA to none. After lowering PH to 7.5 with muriatic acid I started adding bleach going for a target near 10 FC to SLAM.
Most of the algae on the bottom and side has disappeared but a couple of stubborn stains on the bottom at the shallow end. I don't know how high to take it without causing harm.
1 gal bleach last night, this morning recorded FC 8 CC 0
Added 1/2 gal bleach and 2 hours later FC 7 CC 0
My understanding is that I should see ALL algae gone. I scrubbed with a brusch and the couple of stains remain. Should I buy, add CYA now or raise the FC up to 10 first?