I've raised mealworms for quite some time and they are as difficult or as simple as you feel like making them and like already stated, they have no smell at all unless you over feed them with fruit or veggies and leave it to rot. But if you use carrots or celery it dries good without mold generally. I use those or apples. Mine love apples, I can cut a few apples in half and throw them in then come back in a few days to dig out dried fruitless skins.