We've had a recurring algae problem (green) for most of August and September. My DE filter keeps not working after I circulate and I have to tear down and hose off and add more DE. Well I'm out of DE and we've had so much going on lately that once again, our pool is filthy dirty and green on the bottom. I vacuumed best I could before my filter was clogged and wouldn't work again (and pool store near me is closed for the season already and I can't find DE anywhere else........HELLLLLLP). The leaves have started to fall (and we have TONS of trees above our pool) so we put the cover on it and said "FORGET IT!!!!!!!!!!!!". Every spring I open to a green pool anyway and have to clean it up (always cleans up very well with lots of vacuuming/bleach), so what is the difference? Our temps are in the 30's overnight already and barely hit 50-60 during the day (NE OHIO). Did I make a HUGE mistake? We haven't drained the water yet (just incase I absolulely must close with a pristinely clean pool), but with everything else that's going on, the pool is pretty low on the priority index. Opinions?