Performed a chemical analysis this past weekend suspecting CH problems now that I have scale for the first time in 12 years. FC & CC = 13, pH = 7.5, TA = 100, CH = 330, CYA = 120 ( I know this is high and am working to reduce it). So my question is why do I have a scale issue if my CH is within acceptable levels. In addition to scale at the water line, it is also forming as high as 2-3 inches above the water line (like it is leaching up the grout). If my water is balanced , is use of a scale preventer the next step?