When the pool store closed my IG vinyl pool last year, it was not terribly clean (algae) and they did not clean it before covering it. I have been very bad and not kept it up the last several weeks; it is pretty green now. Do I need to get it clear again before closing? I've also never put anything in it over the winter, even when the temps are mild (Oklahoma). I'm reading here all the things other folks are doing to/putting in their pools in the fall & winter and feeling like maybe I'm missing something??