.Thank you — that’s very helpful! Do you have any rough idea of sort of order of magnitude of the weight of say typical light scaling per sq. ft. of surface area or say about half of an average pool? At 8 ppm per lb, at 3 lbs., that becomes very easy to measure and seems like a good indicator that “something” is happening, but nothing so drastic as to damage the finish.
Wow, that is extremely helpful! Scale is not thick, can’t be as much as a tenth of a mm, just a sort of surface discoloration and, hard to describe, like a stuble “dirtyness”, in areas which pieced together would be about half the pool surface. I’m not even positive it is scale. I suspect scale because more obvious scale formed on the ledges where the water gets very warm, and for the first two years of the pool’s life, the pool service managed chemistry by checking with test strips while I never saw them add anything to the pool. At the end of the second season I bought my own test kit and the ph test was a very attractive shade of deep purple (other chems were within reason though). At that point I figured I couldn’t do any worse than them
.Got the SEM out of the attic and estimate the scale at about gold leaf thickness, .12 um, +-5 nm
. Or maybe thin coat of paint, 30 um or so — both wild guesses lol.Would dissolving that one pound of scale have other observable effects — like the additional freed up carbonate ions raise pH and TA? My latest acid addition did raise CH by 25 (but my measurement is +- 25 anyway) and also pH rose faster than usual with TA remaining stable. Ordinarily the pH would not rise that fast and TA would decrease a bit. Maybe dissolving a little bit of scale is working (or maybe I’m just dissolving a little bit of plaster lol)? Again, thanks for your help.
