Wow, This is really cool! I'm going to have to try this someday.
you can try also for these ping a mineral substrate
It has been awhile, but the plants seem fine. 3 of them are in dormancy. A couple are like succulents and the other is more like a cactus. I removed the pin holding one to the side of the rock, and it didn't fall off!
My grow list: http://www.terraforums.com/forums/gr...ght=patrickntd