A Theory About Rising pH in SWG Pools

[KurtV]

Richard,
I hadn't intended this thread to focus too specifically on my situation but here's the last three weeks or so of my testing (CYA 30 ppm and calcium hardness 220 ppm throughout this period, daytime water temperature between 89 and 92 deg F, about 2800 ppm salt but no SWG):

Date pH Alk. Acid addition
7/26 7.8 100 24 oz.
7/27 7.4 100
7/28 7.8 100 16 oz.
7/29 7.7 100 16 oz.
7/30 7.2 90 32 oz. (before testing)
7/31 Vacation
8/1 Vacation 16 oz.
8/2 Vacation
8/3 Vacation 16 oz.
8/4 7.8 90 28 oz.
8/5 7.6 80 16 oz.
8/6 7.6 80 16 oz.
8/7 7.4 80 8 oz.
8/8 7.6 70 16 oz.
8/9 7.6 70 16 oz.
8/10 7.5 70 16 oz.
8/11 7.3 70 8 oz.
8/12 7.4 70 16 oz.
8/13 7.6 70 16 oz.
8/14 Work trip
8/15 7.6 70 16 oz.
8/16 7.6 70 24 oz.

Sorry about the format, couldn't get it any better than this.