If you're intent on keeping them indoors then buy the biggest Frabill styrofoam worm container that they make and spend the money on the bedding unless you have some really rich compost. I've kept them for months that way in my cool garage. I make the compost and they eat the stuff, no need for buying worm food. Now I just let all my extra crawlers go into the compost pile in the backyard and all I have to do is dig some the night before I go fishing. Cheaper and less stinky in the end.