Before doing anything, you need to verify that your pH reading is accurate by testing when your chlorine is below 5ppm. When chlorine is higher than that, it can cause falsely high pH readings. (If you are using a Taylor K2006 kit, pH readings are reliable with chlorine levels ups to 15ppm.) If it is indeed high, then do lower it with muriatic acid as Carl stated above but please read the tab in my signature about using muriatic acid safely.