Do morio beetles HAVE to live on a grain-based substrate?

[Wayfarin]

They don't require any substrate. I've kept mine in a plastic file cabinet thing (ill attach pics) with holes drilled in the bottom for the worms to fall through. I toss in some egg crate for more surface area plus spots to hide. I've kept them like this for years and they've been producing like mad so there is no hindrance to reproduction.
(Sorry no pics on my phone. I'll add when I get home.)

But no they do not require substrate.

Where do they deposit their eggs? Do they lay eggs on the egg crate or the bare bottom?
What did you feed them? Vegetables?

 

[WhiteMoss]

Where do they deposit their eggs? Do they lay eggs on the egg crate or the bare bottom?
What did you feed them? Vegetables?

I use no sub for the beetles. I put in pieces of egg crate for more surface area/places for them to hide.

They lay their eggs on the crates and on the walls/floor.



I feed them carrots and lettuce daily and give them scraps of other fruits and veggies. They'll eat most anything, but the carrots and lettuce also provide them with a water source.