Plume or mold?!?

[mash]

Originally Posted by T.G

A number of molds, possibly all, will fluoresce when under UV from a blacklight, even if the colony isn't visible under normal light.

Learned this the "OMG! I've been breathing THAT? I am so out of here." way due to a former landlord that wouldn't properly maintain his properties.

I have no idea though if plume, certain capas or even the pectin will or won't fluoresce also.

In this case, you don't need to go that far. Round patchy clumps with tentacles = mold.