i used a bed of perlite to incubate my corns i hatched a couple of years ago, it worked out pretty well, i never had to mist my incubator the whole time i was incubating the eggs. but vermiculite, perlite, hatchrite, paper towels if the humidity is right even work. i also know of people using a potting soil mixture, unfertilized of course, and sphagnum moss for incubation medium.