New the the forum, but a long time pool owner (29 years).
16x32 in ground vinyl lined pool (~21K gallons), Seattle, WA area.
Last year I chased combined chlorine, running my CYA up to about 150. I (partially) blame the high CYA it on a dry previous winter, typically we get a lot of rain, which then dilutes the CYA due to lowering the pool. Of course the Pool Store had me shock with stabilized chlorine, and you know what effect that had...
After discovering this forum, I spent the fall/winter getting the CYA level lowered (two partial drainings, followed by letting the winter rain do the rest).
So now I'm at:
I've been SLAMing the pool since Saturday (5 days). It is totally clear (like others have said, I could read a newspaper placed on the bottom of the pool), and I washed the cartridge filter off a couple days ago. Pump has good flow, about 50 gpm, running right now 24 hours a day.
I'm keeping the FC at 12 or above, but the combined chlorine shows as about .2 to .4 still.
I've been waiting for the CC to go to zero, but now I'm thinking it may not. I did shock last year with Potassium Peroxymonopersulfate, but that should be way long gone.
Am I okay, or do I need to keep going?
I also plan to add borates to the pool when this is all done.
Lastly, unless you recommend otherwise, I plan to leave the CH low.