Quote Originally Posted by duraleigh
I'd leave the pH and Alk alone.....7.1 is fine if that's where your pool wants to be.

The CC of 1.2 indicates a need to shock...probably around 30+ppm to be effective.

And, as you already have acknowledged, you are DESPERATE for a drain and refill to manage the CYA and Alk. About two 60%'s will be needed to get your pool manageable.

I'm pretty sure how the CYA got there.....how did your CH get so high?
The fill water is very hard here (19 grains or 325 ppm if I got the conversion correct). That, and using calcium hypo for a chlorinating source I suppose. We drained the pool back in Feb04 and refilled with 50% soft water and 50% hard water. I am planning to connect the fill line to my water softener. I think it will be easier to monitor CH that way and add calcium as required. We have cartridge filtration (no backwashing) so the only water we lose is through evaporation. But here in Tucson that can be substantial I suspect. I'm guessing the cycle is - lose water through evap, then continually refill (auto refill) with very hard water.

What does two 60%'s mean? We have no problems completely draining our pools here in Tucson, so I could do a 100% drain.