Best starting PH?

[BoisBlancBoy]

I've been doing a lot of reading to learn more about the whole process during fermentation. I know all yeasts have their place, temps and times. I know Ph drops significantly throughout fermentation. What I haven't found, let's say for bakers yeast, what is the best PH to start the ferment? I just tested my well water and it's roughly at 6.5.

I've had ferment drop to low during the process and have had to amend the ph to get things rolling again. I'm just trying to make sure I do the best I can to give the yeast a happy start.