I have a Hayward 6020 DE filter 2hp 2 speed pump & Goldline 40k SCGS I installed 2 1.5 weeks ago. I first added to much salt 4400ppm. I drained 2.8ft of pool water not quite 1/2 the pool. I added fresh water to refill pool. The digital read out shows my salt is 3500ppm but the test strips 4120ppm. This si a big discrepancy I think. I had water tested at pool store there test was 3800ppm with same strip as I used. i am draing 2 more feet to get salt to < 3500ppm.
My question is why is there such a differance in strip to system read out? Can the P4 display be calibrated if test strips are correct. I also have white flakes floating in my pool/spa dose anyone know what this might be. It started a couple days ago. The are soft and break down when rubbed with you fingers. I have other Qs but this will be enough for now. PH is 7.4 and FC is 3.0 or higher TC=1.5 according to pool store.