Thanks for the pH explanation. I used 3:1 ratio because 2:1's results were difficult for me to read. At 3:1 dilution, pH =7.6

Yesterday: FC went from 32 (morning) to 29 (early evening), and CC stayed @ 2.0. So I added approx. 24 oz of bleach (I figured about 1/5 of a jug) to bring the FC back up. At 10:30pm FC=31 CC=2.0

This morning @ 6:30am FC=30 CC=2.0

I decided to use the 2 scoops of DPD. Glad FC is holding, but darned frustrated about CC not lowering. Rainy day here, but sun just came out. Can't think of anything else to clean!