Last evening the pool looked better, but not great. I vacuumed for the 4th day in a row and took a brush and scrubbed the walls down. I think I will bring the chlorine up to shock level for a few days just in case I do have algae. Last night my numbers were: FC=2, CC=.5, CYA=140, PH was at least 8.2--that's as high as my test goes. I added muriatic acid to try to bring the PH down. I added a gallon of bleach (8.25%) to start to bring the chlorine up. That's all the bleach I had on hand. This morning my numbers were: FC=19, CC=.5, and PH was still at least 8.2. I'll purchase more bleach and muriatic acid today. I think I'll try adding the DE as well, if I can find it. I live in a rural area with no pool stores. I'd like to have this pool looking good by June 18th for a BBQ at our house. How long should I keep the pool at shock level to ensure any algae is dead?