Salt system issue

[daddyoh]

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.

 

[polyvue]

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?

That's a good question, and one that has been discussed here in other threads (you can locate these discussions by using the Google Search built in to TFP -- see the very bottom of this page).
:google:
I have the same type of SWG you have... my AquaChek test strips also show very high salt level compared to the SWG control (P4, PS-8 should have the same read out.) I don't think there's an meaningful way to calibrate them. Right now, I would recommend relying on the SWG to tell you what your salt level is, but remember that it is SLOW to respond to changes... sometimes by a day or two, so be patient. Others will likely respond to your mysterious flakes.

 

[duraleigh]

I have no SWG so am only parroting what I remember from other threads on the forum.

I believe the Aqua-chek Salt strips have consistently been more accurate than the units themselves. I do remember an out-of-date situation but, as long as the strips are current, it seems I remember folks saying they are the most accurate.