12.15.14 pH 6.5, FC 6.5, CC 0, TA 60, CH 1000, CYA 50, H2O t=57 degrees -(13 of 28 oz 12.5% chlor brings to 7.2 FC)
12.17.14 pH 7.6, FC 6.5 -(28 oz 12.5% chlor, 22 oz 14.5% MA)
12.22.14 pH 7.5, FC 7.5, CC 1, TC 8.5
If it's relevant, I have not brushed my pool just besides my steps (4) for about two weeks. Polaris 280 is and has been running every day though. I have my pump running five hours a day. I had lowered it from six hours in the swim season to four hours non-swim season, but I started noticing some algae formation on the steps. As a result, I increased it to run five hours and have not noticed algae form as quick.
Could the sudden showing of combined chlorine be related to not brushing the pool?
What could've caused there to be combined chlorine all of a sudden when I've never had it? I have never let my chlorine fall below the minimum for my pool which is 4 based on my CYA of 50.
Could this be a seasonal, cold weather/water thing?
While it is not swim season, should I even bother shocking?
Could this have been averted had I just brushed my pool weekly? FWIW, I was brushing my pool weekly during the swim season. The longest I have been going now w/out brushing in the non-swim season is approximately two weeks or so.