I wouldn't seperate the adults from the nymphs for long. The newborn nymphs feed off the frass (poop) of the larger roaches until they start eating regular food. They can also take a RIDICULOUS population density. its awesome.

I've had my colony going since january.

Adult males have full wings but can't fly.
Adult females have small wing nubs and can't fly. They have shiny black bodies. I can get some pics if you'd like.