I thought I had posted on this before but I guess I never did. I have always atributed this issue to calcium and I scrape it off but I am not sure anymore. Maybe someone here can help me eradicate it.
It's hard to get a picture but little white splotches appear on the plaster. This happens a lot over the winter when the pool is closed but they do also occur during the season. In the picture you can see the raised spots - all under the tile level - and some of them have a teardrop appearance or like melting wax. It is gritty and can be removed with a scrungie although I cant get them all and they are everywhere in the pool.
My chemistry is pretty much humming at this point but the only thing I grapple with in terms of fluctuation is the pH rising because of my SWG. I typically add MA weekly no matter what so the pH does swing rapidly over the week from maybe 7.2 to as high as 7.8-8.0 (occasionally)
Here are the latest numbers which have been pretty typical (other than the temp which is usually higher like 83 but we were away and the heat was off).
Thanks a lot.