We have a 28' round AG pool. We bought it used and this is our second season. I realize the value of using the solar cover to save chlorine but I really hate the cover. It's difficult to take off when only one person is going to use the pool (which is most of the time). What I had been doing is rolling the cover up until about 3/4 of the pool is exposed. Then I'd flop the two ends over the side to anchor the cover. I'd use the pool and when done, just unroll it to cover the pool back up.
Last week we were having record temperatures and so I left the solar cover rolled up and hanging half out of the pool and half in the pool. Although the pool was sparkling and clean and showed no evidence of algae (thanks BBB) I was using too much chlorine in a day's time. I shocked the pool and found my number would drop significantly through the night. Remember, my solar cover is still rolled up and hanging half in, half out of the pool. After two days of yo-yoing chlorine numbers, I decided to cover the pool back up even though we are still experiencing 98 degree days (my pool is in full sun all day). Imagine my surprise when I saw the brownish-green water being dumped into the pool from the solar cover's folds. I thought aha! That's where the nasties have been hiding. I believe as fast as I was sanitizing the pool, the solar cover was manufacturing algae or whatever so that I could never catch up. My pool is covered now and I started the shocking procedure all over again.
I will now either cover the pool back up after I've used it and not let it hang half in and half out of the pool for days at a time, or I will remove the cover completely.