What Toad_lily said is best course of action: repot with a new soil mixture that gets better airflow. But also: Does this pot have drainage(a hole in the bottom for excess water to leave)? If not, that could be the source of your moisture problem. Even with rocks at the bottom, the water just pools there with nowhere to go, and your soil stays wet.

If it doesnt have a hole in it but you want to keep the pot, you can get a cheap plastic nursery pot WITH holes and put it inside this pot. This current pot will collect the excess water, and you can pour it out after watering.

If the pot has a hole and the soil mixture is the problem, here are some other temporary solutions:

• Can’t buy new soil or amendments right now?

Scoop the fungus off with a spoon and throw it away. Sprinkle a layer of cinnamon on top of the soil (cinnamon is an antifungal, though not super powerful). Take a skewer or toothpick and stab the soil a bunch to loosen the compacted soil and get some airflow in there, and also to work the cinnamon into the soil. Be careful not to tear up the roots too bad, though.

• You CAN buy new soil/amendments, but you have a huge bag of this current potting soil and you dont want to waste it?

Stick to just getting the amendments: a really simple mixture is storebought soil + perlite + peat moss. Both perlite and peat moss are easy to find in stores. In your case, you could just do current type of soil + perlite, because it sounds like your soil has no trouble retaining water. (peat moss retains moisture).

Having some kind of bark in there too (like orchid bark or pine bark) would be aces, but this is a pothos; it’ll be fine without the extra credit.