vanman,

I had the same issue you are having now when I opened my pool. You can look back at my thread entitled "Excessive bleach consumption" and see all of the information I was given. Carl hit it right on the head...you have got to hammer it with bleach. I did 3x a day to get to 15 ppm and it took almost 2 weeks before whatever alien life force that invaded my pool died off. Now I'm on cruise control and add a jug of bleach every 2 days, and my pool looks great. Good luck, as I know first hand how frustrating this can be. I tested when I got home from work and bumped to 15 ppm, then before bed and bumed to 15 ppm, and on the advice of others I would even add an extra jug about an hour later, then in the morning I would test again, bump to 15 ppm. If you are losing chlorine from the bedtime reading to early AM reading [before the sun hits it] then you have something you don't want in the water eating your bleach. Do you have any CC in your pool? The weird thing about mine was I had 0 CC.