CH from fosset water = 275
I have an issue with the grouting on my coping brickwork pitting. As you can see in the pics. I have high CYA so for the last year I've been using 12% Liquid chlorine and Dry acid (to control high PH drift) and nothing else. I did a 50% drain last year, after I fired the pool guy recommended by the pool builder. The CYA was through the roof and still isn't where I would like it to be.
Is the High CH causing the pitting? It only seem to be at the brickwork closest to the waterline. I have the same coping at the top of the bond beam (3+ feet above water) and it isn't affected with the pitting.
Sean (Southern CA)