I recently had a little rust spot fixed in my pool, which meant draining and refilling the pool. The water I get from my well is pretty good, but has high alkalinity and surprisingly little calcium. Since I refilled the pool, I've had the water tested by three stores -- all of them giving me different values, but along the same lines -- as well as testing it myself. Total alkalinity is around 180; PH is around 7.6; Calcium hardness around 220. CYA is around 80. The store I usually go to suggested adding about 4.7 gallons of muriatic acid to lower the alkalinity. I'm not sure why they'd want me to dissolve my walls (marcite on shotcrete), but I thought it best to ignore that piece of advice. The high alkalinity does result in a constant creeping up of my PH, though. Every time I have it nicely balanced, the PH travels up, and then I have to lower it again -- even without adding chlorine or anything else, the PH will move upwards. What would be the proper way of getting the TA to a more acceptable level without lowering the PH to some hideous level?
On a related note, the store suggested that I try shocking with Cal-Hypo for a change -- I usually stick with liquid chlorine -- since it will slowly bring the hardness up a little. That made some sense to me, but as soon as I did that, the pool went from absolutely completely clear to cloudy. Is that normal? It bothers me.
For completeness, this is a 24,000 gallon shotcrete/marcite pool from 1976 in South Florida.