Kurt,

I'll bet that when you hit 50, if you let the pH rise to 7.5 then the continued rise from there will be slow (i.e. you could add acid when it hits 7.6 or 7.7). You could therefore make your pH "target range" 7.5-7.7 and not use too much acid. In fact, the general advice for people with low TA would be to have higher pH for better water balance though this technically is only necessary for grout/plaster/gunite pools. Anyway, thank you so much for keeping such good track of your numbers. It really helps in trying to figure these things out.

By the way, if the TA is somewhat stuck on 60 and getting lowered too slowly, you can always just add some extra acid to get to a pH of 7.2 or below in order to accelerate the outgassing (i.e. Ben's alkalinity lowering technique), but if you have the time and just want to see how things slow down as TA gets lower, then measure on...

Richard