Just had new liner, and converted to SWG. Everything seemed good, but I keep finding brownish deposits and dust on liner. Same as last year, and hoped new water would have cured it. At first thought broken lateral and was sand, but now think that it is mustard. Have read scores of blog discussions on it and want to try to treat for it, in case. After raising FC it seems better, but of course I'm still not positive that it is ... I mean did it just live in my filter over winter and bust out when I started up last week?.
The pool company started it week ago and brought FC up to 10 (with cya 0), which I let settle to about 3 before turning on SWG, and keeping around 3 or 4. Backwashed on Monday and it was dirty, cleaned with the 280 and looked good Tuesday morning so ran filter all day and SWG at 30%. Came home to brown deposits, even more than before, plus sort of sticking to sloped wall (shady side). Fc was around 3, decided to start shocking in case mustard.
Turned SWG to 100%, after brushing. Fc was up to 9 by 10:00 last night and I saw less brown this morning. At 6:00 pm FC was 19 but still some brown. Checked at 10:00 and came up with FC 17 (best i can tell swg would have added at least 2 ppm during that 4 hours, not drop 2)...so maybe I'm killing something?
I can't check cc due to no reagent but here is other
FC..17 and leave swg at 100% all night?
CH - 20
CA - 45
TA - 110
Salt - 3200
PH - was 7.6 but not accurate now, right?
Should I keep going with swg? I'm worried about damaging liner ...could be 30 FC by tomorrow night.