DW had bought me a plastic utility drawer tower at wallyworld when I was raising mealies. It became a 20 tier shelf! the shelves were 4" deep and kept them buggers inside. I had certain drawers for larvae, for pupae, for adults, and for eggs.
Potato was the choice of food, along with oatmeal/cornstarch combo for bedding. My buggers would lay eggs on the bottom of the plastic drawer, so transferring eggs was a sinch. Just remove live into a drawer to keep producing and dead adults to the jettison pile ( bowl for chickens) from the drawer after a week and move into the "eggs" portion of the shelf.
Larvae get moved when they become pupae
Dead larvae go to the Jettison bowl
Pupae get moved once they become adults. Remaining unhatched pupae get moved to another pupae drawer.
Dead pupae go to the Jettison bowl
Adults go into the adult drawers.
Dead Adults go into the jettison bowl.
We keep a moist paper towel on top. It did two things:
Kept moisture in the drawer
Wicked excess moisture out of bedding
We had zero mold.
Leftover potatoes and veggies go into the jettison bowl.