Test your water at night for chlorine, and again in the morning before the sun hits the pool. If you lose more than 1 ppm of chlorine, or if your CC is above 1.0, then you need to shock the pool and hold it until you're not losing chlorine at night. If you haven't lost more than 1 ppm of chlorine overnight, then it's probably just the dead algae that needs to be filtered out.

Do you have a working pressure gauge on your filter? Is the pressure rising as you run the pump? I've looked at the Pool chart, but don't see your info, unless I missed it--if you haven't already, can you take a few seconds and fill this out for us so we can give you better suggestions?

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