I am beating my head against a wall here. All summer I have been battling high PH and alkalinity in the pool. I have dumped enough acid in to bring both down to level and within a short period of time - both are high again. We have a spill over spa and a waterfall. I have turned off the waterfall thinking that this was the source of the increase in PH, but it has made no difference. Because of the heat in Florida - I even tested the hose water and the ph is so low I can't even get a good reading - so I know it isn't there. Here are today's readings
TC = 5
CC = 0.5
CYA = 90
PH = 8.0+ (10 days ago I added a gallon of muriatic acid and the following day it was 7.4
TA = 110 (testing the day after adding the muriatic acid from above - 80)
CH - 300
This has been going on since I took over the pool maintenance last spring. I am usually having to adjust this every few days - It has been ten days because we were out of town. I can't believe how much muriatic acid I have gone through this summer. The pool is not used very regularly - only when kids and grands come about once a month - and the spa is used probably equivalent to once a week. The pump runs 3 hours per day in the late afternoon and the SWG is at 60%.
What can be causing this constant rise in PH and alkalinity?