I have been waiting for cold weather in the Dallas/Ft Worth area before trying the AA treatment to try and avoid having an algae problem while the chlorine level was low. Before starting the treatment, I had the following test results: 0 Chlorine, 7.1 pH, 120 alkalinity, 100 CYA. My pool is 24,000 gal. Before adding the AA, I applied a bottle of Polyquat 60 just to play safe regarding algae. I used 3 pounds of ascorbic acid and did not see any change in the stains on the bottom of the pool after an hour. Since I didn't have any more ascorbic acid on hand, I bought a bottle of Stain Remover from Leslie's which I was told was basically ascorbic acid, and added the entire bottle. There still was not any change in the stains after another 2 hours. In hopes that the stains were loosened from the pool floor, I then applied 3 bottles of Jack's Blue Stuff and ran the filter for 24 hours, but still no change. I then tested the water and the pH was still 7.1. Even if the stains were unaffected by the ascorbic acid, shouldn't the pH have dropped? I'm wondering if the ascorbic acid has a shelf life (I had purchased it 3 mos. ago and stored it in a dark cabinet in the house), yet it seems to me that Leslie's Stain Remover should've still done something. Any ideas or suggestions?