Step 8: The Substrate

For the substrate, I wanted natural looking desert terrain.  However, I didn't want to use sand to avoid any of the animals getting gut impaction from ingesting it.  I decided to use a very small gravel.

I just put the gravel directly on the floor of the vivarium, which is the plywood base.

It has worked fine for the past year.  

When they poop, it dries quickly due to the arid environment.  However, I regret not putting down some kind of plastic or plexiglass on the floor, underneath the substrate.  I am concerned that over time their urine will soak into the plywood and cause the vivarium to smell.  But as i said, after one year it is still fine.