For 12 years, I've been closing my Northern Virginia pool exactly as the pool company instructed: insure chemistry is correct and algae free, draw water down below returns (while backwashing DE filter), drain equipment, install plugs, cover pool with my fitted (but porous) pool cover, throw circuit breaker. This occurs around Labor Day when grandkid visits are over, leaves begin to drop from the poplars on one side of the pool, and interest flags. Over the winter, snow and rain fill the pool back to the rim. In mid to late May the pool is opened, and every year, the dirt and algae removal is gargantuan. It takes three to four days of almost constant pump running, numerous backwashes, manual removal of leaves and other debris (including mice, frogs, even squirrels) to get to the crystal clear pool waters we swim in. I know not much can be done about the animals and tree dirt/debris, as we live where we live. But is there anything I might do differently to discourage the heavy algae growth over the fall and winter? I've tried floating gizmos with chlorine tabs, special pool store "winter algaecides" etc. but never notice a difference. Perhaps as long as I live in the woods, and resist opening the pool very early when the temp is only 50 degrees I am stuck with this situation.