I have been working on getting my water right, and recently dropped TA from 170 to 150 to 125 and now to 100 (at 100 for 2 weeks now). However, no matter what I do, my pH seems to be rising by about 0.2/day. I'll chase it back down with acid, and it immediately starts rising again. After reading around here, I checked for any air leaks and see none (no bubbles whatsorver after the first minute or two of the pump starting up) and no returns breaking the surface. No water feature, and the aerator is off. I also read somewhere that a high TA might cause the pH to rise like this, but at 100, I wouldn't think that should be an issue.
I typically chase pH down to around 7.5, and within a few days, it's up to around 8.0-8.2.
The desired TA number seems to be "70-90+" but I'm not sure HOW MUCH "plus" is acceptable. Should I try lowering the TA even more to get the pH to remain steady? Or is this daily drift of ~0.2 to be expected? I sure hope not, because I'm dropping more acid than an addict.
pH 7.9 (up from 7.5 48hrs earlier)
For acid, I'm using 14.5% MA, and chlorine is liquid sodium hypochlorite 10%. Complete refill about 2 months ago. I'll add to my signature, but this is in the Phoenix area.