So, your compot. It's going to be *very* important not to let those dry out, at all. Personally, I'd put them in sphag if I had to unpot them for some reason (if they're large enough to go into their own little 2-inchers, say. I imagine they'll be in sphag already though, so you may not have to do anything. When they get big enough to repot, you can put them in fine bark, fine charcoal, and rockwool for moisture retention. I'd also keep them out from under your HPS lights until they get bigger, or just keep them at the edge of the light, otherwise they'll fry.