I use a soil-less mix and like 6.3. I vary about .2 in either direction.

Peace, Farmer Rich
Farmer Rich Reviewed by Farmer Rich on . ph, the "correct" range I've heard alot of stuff here and there, but I can never get a definite answer for this question. What should the ph be? I've heard 5.1 - 5.8, 5.2 being optimal. Local hydro shop owner says at those ph's, rockwool actually "melts??" Is this true? He's telling me to keep it 5.8 - 6.8, aiming for 6 and 6.3 being optimal. This is my problem. Rating: 5