Any time you add any pH up or down, (or most nutes for that matter) you are increasing mineral salts in solution, either hydroxide salts or different acid salts. As far as range, some folks get too hung up on perfect pH. I do quite well by just keeping a decent range of 5.9-6.4. True that having everything as perfect as possible is a good thing, but for some of the newer folks they have trouble with all the shit rolling around in their heads. Lot of info out there, (somtimes a little too much), but the truth is just learning basics first, growing healthy plants simply is always the best way to start. Advanced growing is exactly that; Advanced. I started out using cow shit and bag seed in 1979. These days I use a 7ft tent with 2200 watts of light, using Oxygen pot system and scrogging, and produce 3.5+lbs every 4 months. But I sure didn't start that way.
By the way Jorge still knows how to grow good shit, even though he/I is a bit old school. ;)
Peace
RR1