I've used bean beetles for years and never have had an impaction problem. Their exoskeleton is not real hard. They can be use as a staple food for larger dart frogs. Flour beetles are another story. They have a hard shell. With flour beetles sifted larvae are normally used as the frog food. Bean beetles hatch out of the bean and the beetle is used as the food. My wife "outlawed" flour beetles in our house because the flour is to messy.