Thanks to all. This is such great information. I've owned 3 different pools over the last 13 years, and for the first time, I actually feel like I'm in control, and know what I'm doing, and why.

For the last 4-5 days, I've been letting the FC come down to 8, then add 1 gal of 8.25% bleach to get back to 12, then 2 days later I'm at 7.5-8.0. At those FC levels and with CYA>=100, I should be losing around 1.5ppm per day, using chem geek's 15% typical figure.

Since I'm higher than that (2.2-2.3 ppm loss per day), I assume I'm still fighting something in the water, most likely the yellow/mustard algae. But I've checked everywhere and see no sign of algae anywhere. I'll keep checking. My filter pressure is up about 4 PSI over this 2-week timeperiod, so I hope that's the dead algae. I'll clean it out this weekend. Hope I haven't declared victory too soon.

I suppose it's also possible that my higher daily usage could result from the extreme heat and sun we've had over the last week (temps over 100 and no clouds in sight). Bathing load has been light. I'll keep monitoring. 1.2-1.5 sounds very good to me.

Bottom line, I'm starting to like the idea of high CYA... higher FC levels, lower daily consumption, and less frequent manual additions of bleach. Just need to make sure I've killed this yellow beast for good.

Thanks again for all the information and advice.

Mike