I suppose since the pool is in the sun from about 8AM to 8PM is the reason I'm going through so much. On days when it's cloudy, I only need to put one in.
~27k gallons, every night, I measure when I get home and the FC is about 4, sometimes as low as 3.5. My CYA is 50, and CC's always test out at < .5 or 0
According to the calculator, a 121oz of 8.25% equates to raising FC by 3 (which I will prove below), so by putting in 2 bottles, FC should have raised it up to about 10 if it measures 4 in the evening.
Last night I put in 2 bottles, and at 10pm, the level was 8. This morning it measured 7.5. I put another bottle in, waited an hour, tested again, and it's 9.5, so that verified 1 bottle indeed brought it up by 3. That also tells me the level must have been at 2 before I put them in :O
According to this, I'm losing 6 ppm each day when it's hot & sunny. Does this sound normal?
Water is crystal clear, and warm.
CC < .5
Ph is 7.4