A few weeks ago my aquapure stopped being able to generate enough FC (2ppm+), leaving the pool chlorine basically 0 or 0.5. Wound up replacing my aquapure cell but still couldn't keep up given a 100% production rate for 8 hours. I was used to just 20% production rate, as we keep the pool covered.
So I started a SLAM about a week ago but have been unable to complete the SLAM.
My CYA is about 65 so I was SLAMing with a target of 28ppm. Now my water looks clear but I still get a few fistfulls of what looks like dead algae forming at the bottom of the pool every few days. And just when my FC looks stable I fail overnight loss and read significant CC too. Any idea why this keeps oscillating?
I'm testing with taylor FAS-DPD, and for example, I get:
10/18 8am: 38 drops reagent for FC, 12 drops CC (19ppm FC, 6ppm CC)
added 2 gallons sodium hypochlorite 12.5%
10/18 3:30pm 78 drops reagent for FC, 0 drops CC (39ppm FC, 0ppm CC)
10/18 6pm 77 drops FC, 1 drop CC
10/19 7am 44 drops FC, 13 drops CC (22ppm FC, 6.5ppm CC)
Is there something wrong with my tests? Some of those CC counts are so high that I'm below the 10X rule for breakpoint chlorination, even though I'm above 40% of my CYA. Have I hit the "point of no return"? Yet my water looks clear...
I should add, my spillway trough is a bit of a plant-debris magnet, I had to
clean a bunch of leaves out of there during the SLAM, but now it's as clean as I can get it without pressure washing.