Soil pH buffer?

Thinking about to start a new grow, due to the last one messed up, so I'm thinking about using the Plant Magic nutes, and a few people are saying not to pH the water, since the soil and the compost buffer the pH, but my tap water pH is around 8.5, that's way too high in my own opinion...

So, any thoughts? Since I'd be using organic PM Oldtimers feed, mixing with chemical pH up/down doesn't seem like a good idea either

Any help would be appreciated