Thank you for the reply waterbear. The water is now balanced. I do not know how it became soft over the winter but that is how it read on the testing and the evidence of the eaten grout confirmed it. The pool was built in the 70's and we got the house after it went through a 2 year foreclosure. I do not have all the information I would like about the pool. It is painted plaster but I do not know what type of plaster. Maybe quartz? Looks to be a shiny bright white where there is a chipped spot just below the tiled water line. The tile section is from the coping stones and goes down about 6 inches. The waterline falls about midway on this tile part. If it were lower then the water wouldn't make it into the skimmer.
Do you know of anything to preserve the grout for a little longer?
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