u/Certain-Schedule9397

Pic just for attention

So I have 2 takeaway containers with approximately 100 seedlings that are approximately 2 months old. I opened the containers for the first time today. Seems I have a mold/fungus issue. Can't get pics to come out worth a damn to show. Seems like a very fine brown hair like growth mainly around the edges of the containers. Substrate is approximately 80% bonsai jacks inorganic, sand and oyster shell and a rather small amount of leftover seed starting mix I threw in just to get rid of, along with a bit of worm castings. Everything was sterilized. This is my best germination yet and I don't want to lose them. Need advice on what to do. Transplant ant treat with fungicide? Thanks