pH of water going in should be between 6.2 - 6.9. For simplicity consider making your own soil. Stinky's tutorial on "growing da dankness" provides a fool proof recipe. Note that with a soil grow you need to re-pot through out the grow to replenish soil that is depleted around the roots. In other words, don't plant in a 3 or 5 gallon pot at the start and think you are done. Much better to plant in small pots and repot often.

Some measure pH coming out of the bottom but the composition will change as it flows through the soil so I don't put too much stock in that number. Some people swear by it though so decide for yourself.