What is this?

[dvybiral]

Hello Reefers,
I need help identifying what this is , good, bad, and how to eradicate it. I have researched and the only thing I can come up with is spaghetti sponge. It is mostly on my rock and some in my return chamber in the sump. Could it be a flow problem, water chemistry issue, or something else. I don't want to scrub it off my rock for fear that it may spread and multiply even more. Any help would be appreciated. See pics.

 

[Rjukan]

Looks and sounds like some type of sponge. Good for the system, I would leave them be. I have a bunch in my OF as well.

 

[vetteguy53081]

Syconoid sponge