I know this thread is a bit old but I saw a few unanswered questions and of course I cultivate and offer For Sale Roach Bin Cleaner Crews. In these "Cleaner Crews" I offer two forms of larvae and two types of beetles from two species. The first species is indeed dermistidae. The second species are a special form of mealworm that is tinier than common ones and hard to Find. Now, the Dermestid Beetles & Larvae Eat Flesh from only the dead roaches or crickets. The mealworm larvae and their adult stage beetles will eat the excess grains before they turn moldy and become a danger to your roach or cricket colony. They do not compete or take food away from your roaches as they are mainly out of the way and eating stray foodstuffs Because of the life cycle of these larvae and beetles there will always be more larvae than adult beetles as the beetles only live a few weeks and lay eggs. It is the larval form that does most of the eating flesh and excess grain. You will notice between 10-15 times more wriggling larvae than beetles.

My stock of Dermestid and Roach Bin Cleaner Crews are free from invasive species such as mites, red flour beetles or red leg ham beetles which can cause your cleaner crews or dermestids especially to falter as they are outcompeted and eggs are destroyed.

The beetles are safe to use as occasional feeders and as Jeff said not as much for smaller species. However as stated prior these species most often exist iun their larval form which is either a tiny mealworm or a tiny soft larvae, that is useful for stimulating frogs to prey on future live feeders.