TJNav, ton's of people are reporting this exact same situation this year. My dad's pool has it as well. Any chance you have big trees near your pool?

This seems to have been an exceptional year for pollen. If something was growing in your water that fast, it would seem chances are you'd have measurable CC.

A few nights ago I brought the FC way up in my dad's pool (he's on vacation), lost very little overnight and the appearance of the stuff didn't change.

I'm ignoring it from now on