We have had our Solar Cover on for a couple of weeks. Still adding Bleach everyday and water is testing good. Uncovered today..water is clear and tadpoles have moved in. I've read on another forum to Shock, but what else? How long do they take to die? And how do we prevent this from happening again? I'm afraid it has to do w/the cover being on for so long and the temperatures have been upper 90's! I've been so proud of our clear water!