I'll have to go with skunky on this one. I have hydroton rocks and yes they do shift very easily. I would go with lava rocks for the same reason skunky posted.
They also hold beneficial bacteria well too. Next grow I'm going to try lava rocks. Only problem is I have this HUGE bag of hydroton.
Gen Reviewed by Gen on . Can you use red lava yard-rocks for grow medium ? Iā??ve heard people mention ā??lava rocksā?? as a grow medium, instead of Hydroton. Are they talking about special lava-rocks sold at a grow store, or the red lava-type rocks used for landscaping, that people use in their front yard in place of grass ? The yard kind is probably very cheap compared to Hydroton (they probably sell it by the cubic yard like soil). What I wonder is: 1) does it release minerals into the solution that would raise/lower the pH ? and 2) does the rock being red Rating: 5