I think I have this under control. But I would appreciate clarification/reassurance...
I tried to raise my PH from 7.4 to 7.6.
My TA was 80.
Using the pool calculator, I added the proper amount of Washing Soda (which also told me the TA would likely rise 6.4)
24 hours later:
My PH went up to 7.5-7.6 (where I'm aiming.) but my TA went up by 25 points to 105. I understand now that 105 TA is not a big problem. But I'm disappointed that it jumped so much.
The big questions:
Should I only worry about TA if PH gets too high?
Should I trust the pool calculator's "Effects of adding chemicals"?
Now playing with the calculator, I see that Borax would have less rise on TA for the same PH rise. But I'm not sure how much to trust the "Effects of adding chemicals" after the rise in TA last time was 4x what was predicted.