You dont put water and they go as same?I breed them. I find them exceedingly simple. But I don't do the sorting and sifting and all that. I even stopped giving them water a few months ago when it occurred to me that bugs that infest grain aren't given potatoes.
I put them in a small tub, add some oats or whole wheat flour (or both or whatever grain you like), stick them in the cupboard and forget about them. It works. If you feel like cleaning out the tub, just put the beetles and pupae in the new tub, and the mealworms as they pupate. Takes a little time to switch over, but pupae and beetles stay at the top so you don't have to sift for them.
Dubias are just as easy, but produce more.