whats the PH of the plain water your using, and whats its ph after youve added the nutes?

going off what you said, i would say a good flush now and then should keep your soil/run off ph under control.
its less complicated than using an addetive to bring the ph up, and better for the plant, i belive.

as long as you have reasonable drainage, dont be afraid to give them a good flushing, i do it quite regular, but try to use luke-warm water to avoid stressing the plant too much, i do mine in with a shower head in my bath tub, lol

as long as you let the plants dry out for a few days between heavy waterings, and your drainage is good, then youll be fine.
what you dont want is water sat in the pots rotting away.