I have been a TFP voyeur for a couple of months now. I found this sight while searching for answers to Black algae solutions. I bought a TF 100 test kit. I drained my pool by 60% + to get my CYA down from the 100 level that it was at. I have been slamming for three weeks now. Water looks great and I think the algea is fading slowly. PH and alkalinity have been creeping up. I know the PH will read high during slam but should I reduce the alkalinity? The alkalinity was 100 when I started and the PH was 7.5. I think it is going to take a few months to rid this black algae as it was there for 6 or more months before I knew what it was. Do I really need to keep it at slam levels or just an elevated level and can I back off the pump from running 24/7? I have also been scrubbing with a wire brush every day. Current numbers are as follows.