I have not checked readings since November. We're just at the point here in PA where the water is starting to freeze over on the surface. Last year, with the new plaster, I was worried about scale and so several times had to lower the pH. Now, however, I seem to be looking at the opposite problem and am concerned about etching. I'm getting an SI of -0.9 due to the following readings
pH - 7.6
TA - 60 (can this be right?)
CH - 100 (can THIS be right?)
TEMP - 42
I took the sample right from the skimmer bowl - which is not always entirely accurate but generally close. Also, the pool water level is up over the tiles and so I am theoretically sampling 'pool' water and not just accumulated rain water in the bowl. How could I have gone from CH of 190 back in November to 100? And how from a TA of 95 back in November to 60? I almost have to pull back the cover part way and get a sample from the pool, but might not be able to if there is too much ice.
Should I be concerned, or just leave it as is? I don't think I can adjust the CH with the water being this cold anyway (?)