Richard, I guess I am still confused...but still happy. Here's my observations.

Referencing your chart, over the last few years I ran TA at ~100 and tried to keep pH around at 7.6. Your chart shows this as 0.67 relative value. During that time, I had to add acid weekly to keep the pH in check. This spring however, I ran TA at 40 and pH at 7.1 (because I thought it would come up naturally but didn't). This has a relative value of 1.04 on your chart. So if I understand your chart correct, my pH should have risen faster this spring than in the past few years, however this spring my pH did not change at all for 6 weeks and then it only changed when I added borax.

Another observation is that you calculated that I needed about 4.5 cups of borax, but I added 5 initially because I have more volume due to a concave pool bottom. Initially, this did bring the pH up to ~7.5, but within a week it was back down to ~7.2. I added borax weekly until now it appears my pH has stabilized at 7.6. But it took 1.75 boxes of borax. The boxes are the standard home size weighing about 4 pounds each. It does not list the volume. So for some reason it took much more borax to get my pH up. My alkalinity is now up to 60.

As I said however, I am happy. I don't worry about alkalinity and my pH stays constant. I just maintain chlorine by adding bleach and everything is fine.

As always, your insight is very interesting.

Thanks,
Jim