It could be either one.
The two are very similar
Anyway, they won't do any harm to your plants.
- Adrian

If it grows like a bunch of tiny Christmas trees, it is moss. If it grows as a bright green thin layer, like a short carpet, it is algae.

If it is yellow, grey, or white, and grows fibres and round spore bodies, it is fungus. Kill the fungus, ignore the moss and algae. (unless the moss is Spanish moss, not likely since it grows on trees, which kills carnivorous plants.)

Good moss:

{{gwi:555797}}

Bad moss:

{{gwi:430819}}