Switched my pool (20,000 gal.) recently from Pristene Blue to the BBB method. I am having problems getting my FC up. Just yesterday I put in 2 gal. of bleach and 1 lb. of clorinated shock. This morning my FC level is 0.5. Other readings are: PH 7.0, alkalinity is 120, cya is approx. 100.

What do I need to do to get my FC level up and what level should I be at? Thanks in advance for any help.