rockwool cubes and pH

[grorock]

I've got small rockwool cubes in grorocks. This is my first time around the hydro block, but next time, its grorocks only. But for now, I know the alkaline ph of rockwool. What I dont know is how I should take my ph reading. Basically, when my ph is say 6.0, should I assume its 6.5-6.8, and bring it down to 5.5 to compensate, or is 6.0 actually 6.0. The cubes have been in the system for 2 months now. I've kept the ph around 5.5-6.0. Thankyamuch!

[Ron]

I would just keep it at that 5.5-6.0.