I thought that last year I read that you can re-test for FC about 2 hours after adding bleach (in front of returns). If that is true, then I'm getting some good bleach from Dollar General. I tested at 6:00 pm and the FC=2. I added 182 oz of bleach. I re-tested at 9:00 pm, and the FC=9. According to the Pool Calculator, 182 oz of 6% bleach raises FC 4.2.
I tested at 2 different spots (one in the shallow, one in the deep) across the pool from where I added the bleach.
The same thing happened when I tested today. Not that I am complaining, but I would like to know if I am actually using stronger bleach than I am paying for, or if I am not waiting long enough for the bleach to circulate.