The following video was done to demonstrate Bioturbation without and with soil fauna.
For that purpose the soil on the left was heated in a oven to kill the soil fauna. Mold spores however survived this procedure:
You can clearly see how much mold growth on the left, while you don't see any mold on the right.
That's why I don't sterilize any soil. The soil fauna will prevent mold from growing and mites and other potential harmful animals have never been a problem for my ant colonies so far.
Edited by Barristan, May 5 2019 - 3:14 AM.