ID Please-Green worm like thing grows on rocks then ends up floating in tank

[Corriebh]

A little bit ago I noticed something in the rocks that looked like a green worm. It was growing on the underside of the rock. Then a few days later I noticed the same thing floating in the tank and clogging up my power heads. I pulled the rock, pulled the stuff off, let the rock sit to kill off anything on the rock and put it back into the tank. Well whatever it was came back (could be from the original rock or could be that it spread before I could pull the first one). Now it is constantly in there, doing through the same cycle, popping up on the rocks, becoming detached from the rocks, and then ending up in my power heads. It doesn't seem to be impacting anything, but I am curious what it is. Searching for "worm like thing in aquarium substrate" is like trying to find a needle in a haystack. I did pull some off a rock and put it into a dish and took a picture.

 

[cloak]

It just looks like some sort of macro algae IMO. How does it feel to the touch? (rubbery, wiry, slimy etc)

 

[azcrazy]

looks like cheato macro algea

 

[Corriebh]

When it is dry it is sticky. Doesn't seem too slimy unless it is wet which is when everything feels slimy

I do have cheato in my refugium and in a 10g tank that I grow copepods in and it doesn't look exactly like that. This is a bit lighter in color and seems thicker. But there could be all kinds of different cheato that I don't know about.

 

[BlueRoofTang]

Yeah, looks like chaeto to me.

 

[Newstead]

I get small pieces of chaeto sometimes from the HOB refugium on my 10 gallon QT. It does appear lighter than the chaeto in the fuge, so I bet that is where yours is coming from as well.