To re-establish sand and rock you do not need good lights or great flow. I would ghost feed a bit to create a cycle. I would add a hang on skimmer just to get rid of some of the crap that will come out of the sand ( yes its live- but moving it around from one tank to another will absolutely release a ton of dentritus, etc.) and maybe rig up a DIY temporary way to push the tank water thru a filter sock or some type of physical filtering media.