Mushroom Parasite?

Some of my mushrooms are infested with what looks like a parasite, but I
can't find any information on them. I have several different types of
mushrooms, but the infestation seems to be limited to one or two types. The
ones they're concentrated on are dark grayish-green and have a fuzzy
canvas-like texture. They're also on some of the red and the reddish
multi-colored mushrooms. The parasites are slow moving creatures that seem
a little larger than the head of a pin. They're about the same color as
pink coralline algae, and they're almost translucent. They seem to move in
a slow squirting motion. They look like the same creatures I discovered in
my refugium several months ago, but those were a clear translucent color.
None of the other fish or corals appear to be infected, and everything seems
healthy. My reef has been up for almost two years, and other than a few
bouts with ick, I've never had any significant parasite problems. These
things seem to be on the verge of exhausting some of the dark mushrooms. I
hope they don't spread. I haven't plucked the mushrooms yet, but it's
looking like I'm going to have to do something pretty quick. Any help is
appreciated!!
Royce