I believe lava rocks might have nutrients and other materials stick into their structures and might get released later. I'm not sure about this but if lava rocks really do some from volcanoes then I'm sure they would have something in them that might make pH or ppm level fluctuate later on. I would just stick with the hydroton and stay away from the rockwool since Zandor hates it so bad for the same reason I think lava rocks might be bad. Goodluck <3
Da1KrayzieThug Reviewed by Da1KrayzieThug 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