Well... I'll chime in with something different, just to be different!
I've got a QT set up to house new arrivals as I stock my main tank. While it's bare bottom with PVC
pieces, I do have a 5-6 lb chunk of live rock in there. It's just base rock, but at least it gives the new arrivals something else to look at other than PVC
. The royal gramma that's in the QT now really likes it! But as far as using that rock elsewhere, it's only purpose is to stay in the QT. If I have to use copper sometime, I'll just throw it away afterwards.
But I will agree with everyone else on one point - I'd sure leave the bottom bare for now if I was you. Two reasons: (1) it's easier to keep the water parameters great by sucking out the gunk now and then off the bare bottom. In a smaller QT, it doesn't take much to get your nitrates up there. And (2) I didn't plan to use meds in my QT tank either, but I did. SW
fish are a bit touchier to stress than FW
. Substrate just adds one more thing that can interfere with the meds in a way you can't predict. Adding sand later is easy enough.