OK Ben, I got the rest of the in floor heads out today and cleaned their outlets as well as possible with a brush. I had the water tested for phosphates and as I remember it was high. 500ppm or more. I think it was the last color on the scale they were using. So, do you think the phophates are feeding the algae problem. Of course they wanted to sell me their phosphate remover. I figured I'd wait until I hear from you. Eventually I'll need to fabricate a cap for those floor outlets with small holes in them so that no one gets a toe or hand caught in them.

If you recall my other thread in equipment, I'm also about to replace my 12o sq ft cart filter with a 320sq ft one and new pump, but am thinking I need to clear this up first. I've also got high alkalinity and high Calcium hardness, don't know if that's making anything worse also.

My FC was 16 this morning with a CC of less than 0.5. The yellow dust is now blue grey, water is clear with a slight haze. I'm brushing daily. Typical for this point of my shocking. My plan was to put the Chlorine to 25 to 30 now for 3-4 days. Where would you suggest I go from here with the phosphates etc.

Thanks again for your help.