Test results on new pool in Tucson

[SunnyOptimism]

If you have a concrete pool, lowering the carbonate alkalinity may not be something you want to do. Aeration raises pH by lowering acid carbonates (carbonic acid and dissolved carbon dioxide). This in turn results in reduced alkalinity (bicarbonates and carbonates).

Also, the note about the bleach products was just a caution -- I really had no idea whether it had been an issue for you.

I'll chime in on aeration by saying that I leave my spa spillway running along with the pool (one return to the spa and three returns to the pool, 50/50 split on the three-way valve) and I run my waterfall 2X per day for 45 mins at a time to make sure the basins in the waterfall always "see" chlorinated water everyday. With all that, my pH sits happily at 7.7 and rises every 3-4 days while my TA is solidly 70ppm. I don't like to drop my pH much below 7.6 or else my CSI get s a bit too negative for my comfort and my alkalinity drops.

If rising pH is a problem for the OP, I would suggest adding 50ppm borates to the water to help control pH. I did back in August and my acid additions went from every other day to once or twice a week. Before borates, my pH liked to sit at 7.6 (seemed to hover there and then rise) but now it likes to "settle" on 7.7 for a few days before rising.

Please Note - Adding borates DOES NOT REDUCE the total amount of acid needed to reach a certain pH level. It only lengthens the intervals between acid additions. SO you will still be adding as much acid as before, just not as often.