We moved into our home three years ago. Our plaster pool's Calcium Hardness has been steadily increasing from 450 in AUG2012 to 525 in JUL2013 to 650 today. I am not having any problems with scaling except for around one piece of granite stone on the spa overflow which has been there for at least two years. It has not spread or gotten any worse. The pool looks great.
My question is, how hard is too hard?
My tap water has a CH of 200. Should I do a water change, or not worry about it since all seems well?
My Test Results Today 04/17/2014 using Taylor K-2006C
Water Temp: 72
I know my CyA is low, but I wanted to get this question answered before I add the acid, in case I need to do the water change.