I am so glad I found this forum. I just finished reading everything in "Pool School". Funny how a particular local pool store says it doesn't matter how high your CYA goes. It all makes sense now; they sell more chlorine. Anyway, I have never had my FC as high as it should be, and I am going to give it a go to kill what's left of an algae bloom. Just wanted to say thanks to evryone who contributes to this forum. It is a ton of knowledge, and I was sick of learning expensive, illogical techniques from the guys at the pool store. I think I can get it under control now.