Here we go again... I started late this year on purpose. I just pulled off the cover today and watched all of the remaining mosquitos fly off and what a mess! I dumped two gallons of chlorine into to the strainer yesterday just to knock those buggers back first before pulling the cover. Anyway, It looked a lot worse an hour ago because the photo below is after brushing a lot of the crap off of the walls first. The water was completely dark green yesterday ..