First time posting and love this board/forum so far. I need similar help with my CYA. My pool is 20k gallons and was resurfaced 2 years ago, which (of course) required a refill. Now, 2 years later, the CYA is already at 330 (per a test done at Leslies a week ago). I knew there was a problem with it because every time I test it, the FC is extremely low or 0 no matter when I last shocked or add new tablets. I can't believe the CYA got that high in only 2 years.
Because of this, I decided to pursue the BBB method outlined here, but first I need to get rid of the algae, which is (thankfully) only 2 weeks old, not a season's worth. So I drained 70% of my pool's water and refilled over this past weekend. I just got back from testing the water at Leslies, and the CYA is 100--still too high to begin BBB or clear the algae. What happened? Do I have to drain it again? Please tell me no. For what it's worth, the pump has not been running for a week.
Any help much appreciated.