HELP! Is this a mold or fungus of some sort and is it harmful?

this is my first terrarium that I left for a few days before adding plants. I just noticed some small fuzzy white specks around in the soil layers. is this some kind of mold or fungus? and how do I get rid of it if I need to.

i dont have any springtails in here and no plants or livestock. soil is miracle gro potting mix mixed with a ton of sphagnum moss and some aquarium charcoal. please help! thanks