Thanks, that makes sense. After another day of reading the site, my confidence level of being able to solve this problem is definitely going up.

I shocked the pool the last 3 nights with 6% bleach. I didn't think to keep those levels throughout the day because I figured the sun would burn it up. But going forward I plan on waking up at dawn and shocking again if necessary before the sun gets too strong. Should that be enough or do I need to be adding chlorine throughout the day?

I just got my K-2006 kit in the mail and I should be getting more accurate readings. I will post back my progress.

One more question: I have been shocking at 15ppm levels. Any benefit of shocking at higher levels? 30ppm? 50ppm? What are the downsides? I do have a vinyl liner. Is there a level that I should not got higher than for a vinyl liner?

Thanks again for your help. My spirits are definitely up.

Jim