I am using trichlor for now so I can understand my pool better and how to deal with vacations. Using trichlor I experienced as expected ph drop and was using borax to raise pH and get my TA above 100 via baking soda. Then I got a very small suction side air leak cause returns to be ever so slightly burpy.
During this air leak my pH maintained a SOLID 7.7, didn't have to do anything, this went on for a few weeks still using trichlor. The air leak was actually raising the pH by the amount lost to using trichlor. Once I fixed the leak, low and behold my pH started dropping and is now down to 7.4. Pump runs 24x7.
I'm thinking there HAS to be something you could put on a return to cause this kind of airation (TINY bubbles) and help folks when they're trying to lower TA (get pH down, then raise pH via airation). Or get drastic (and I'm not suggesting it), purposefully cause a tiny leak on your pump basket.
Trying to give back,