Hi Aylad,

My CYA reading (dot test) was ~ 48ppm, pH=7.2, chlorine after 3 hrs of running SWCG (10:00 PM) was between 1-2 ppm, total alkalinity~200ppm.

Honestly, I never measured CYA, or anything other than pH with the other chlorinator the last several years. It was that dependable. Once I got the pH in range, & added the correct amount of NaCL at the beginning of the season I didn't add anything else all year: no stabilizer, maybe minor pH adjustments one or twice per season=crystal clear water with appropriate chlorine conc..
After pool season I drain the pool and store it.

As far as CYA earlier this year (based on the local pool shop....after reading your article on this forum I'm not sure what they are worth) 6/8/2012 CYA=10 ppm, 6/18/2012 = 25 ppm.

I tested the water right in front of the jet, where the chlorine conc. should be the highest and it was ~ 2 ppm.

I can check in the AM to determine chlorine loss, however there is an extra variable: the SWCG runs in the evening, so the chlorine should increase from now to the morning. If something was scavenging the Cl2, then the extra Cl2 produced by the SWCG could mask that effect. Anyways, I'll try to measure it tomorrow AM.

Thanks for the feedback. Unless you have other advice I will probable shock the pool tomorrow. How long should the kids wait after shocking before swimming?

Thanks,
Rob