Q.White Spots On Soil, Weak Seedlings
Hi! I have some seedlings that were growing really well in a mini plastic greenhouse indoors. Then a few days ago white fuzzy stuff started appearing on them. I looked online and saw it could be mold so I propped the top open for airflow and started only watering them when the top was dry so it wouldn’t be too moist. But now there’s little white balls on the surface of the soil (which were definitely not present in the potting mix originally) and some of the surface has turned a light brownish gray shade and the seedlings look weaker. Is it a fungus? A mold? Can you help me identify it and teach me how to cure them? The seedlings affected are Chamomile, English thyme, sweet basil, parsley, and rosemary. I was hoping to transplant them into pots today, but I would like to get rid of whatever is afflicting them so it doesn’t spread to the new pot. Please help! Thank you!

Certified GKH Gardening Expert
It's a fungus from too much moisture. I would turn the tray around so the light is on the other side and they will straighten up. Increase the air flow even if you need to add a fan. You also can thin the seedlings since there are multiple ones growing in each cell.
Here are more tips:
https://www.gardeningknowhow.com/garden-how-to/propagation/seeds/seedlings-after-germination.htm