First off, I just want to say how helpful this site has been for me. Y'all are a Godsend for real!
So here's my situation...
12,000 gal IG pool, vinyl liner. Hayward pump and sand filter. Very very very (emphasis on the very) high water table. Like 2 feet. Essentially, I live in the swamp. If we get a lot of rain, which we have this year, my liner with the pool full of water, floats up. But that's an issue for another day.
So my pump when out when I was on vacation last week. I came home to pretty much a green pool. I though this was strange since I shocked it good and left some pucks floating while I was gone. I though for sure there would be enough chlorine to get me thru the week even with the pump going out. I went to the pool store for a new pump and took my water sample in. My CYA was thru the roof. Like probably over 200. And my pH was under 6.5. Pool store guy told me to drain 50% and refill and bring a sample back. Instead I found this place and began to drain refill drain refill bleach drain refill test.
I think I've gotten rid of about 50% of my water. It was tough to do with the high water table.
Last night at 10 I dumped a gal of bleach in and left the filter running all night.
Today at 11 I tested and these are my numbers (using Taylor k2006)
CYA - 85-90 I'm going to try to manage at this level for now. I need the pool open this weekend.
PH - still low. Added ph-UP just a little big ago. Will retest in a few hours.
TA - 40ppm
The water looks good. It's no longer green (vacuumed most algae to waste during draining) just a little bit cloudy. I think I am on the right track, but would appreciate some additional pointers. I know I still need to lower my CYA, but hoping I can manage for now. Plus, we get a ton of rain which should help with additional dilution (wishful thinking maybe).