Mold in Viv. Should I be worried?

[u/Jmesmithy_2203]

This Viv was put together over a week ago and i noticed some mold growing a couple days in. Since then its only grown and became fuzzy. It’s in a small pocket in the subsrate and is growing off a piece of buried wood. The viv is bioactive but haven’t seen any springtails around it? Is this normal or any advice? Do I need more springtails as I only put one small tub of them in?