What are these 1/4" stalks on my rocks?

[matlet]

I have a spreading growth of these 1/4" brownish/reddish stalks (width of a toothpick) growing on my live rock. They don't seem to be harming anything that I can tell, however I have a few that are growing on my candy-cane coral up near the meat part. Anything to worry about? Sorry no picture - camera busted last week.

Mark

[kbxiong67]

I have those guys too...I have no clue what they are.

[dme330i]

Sponges

[akula]

actually I think they are more of a worm. you may notice at times that they extend a "hair" to grab particles from the water. harmless as far as I know.

[sally]

Could they be hydroids? Are they reddish looking little feather duster type things?
PS. The fact that they are spreading makes me think they may be hydroids. If they are hydroids...you do not want them.

[kbxiong67]

what's the harm in them? They are red in my tank

[sally]

If they are hydroids, they will spread and sting corals and fish. They could be something other than hydroids though. Without seeing a picture I can't say for sure. When I see them in my tank I take a toothbrush to them and siphon out what I have brushed.

[dme330i]

Does it sound like this from WWM:

Creature identification - sponge 9/14/03
Hello everybody!
(howdy)
Every day something new comes up in my new LR. What I noticed in the last few days are some "creatures" which stick on my red microalgae but also below a live rock. There are about 10 already. They look like worms and are small (half an inch or smaller), fat and hairy and with a "mouth" on one end. I do not know if they should be removed or are "innocent" for my new reef.
(they are harmless if not helpful: they are Sycon sponges)

[sally]

I just looked up in Vol. 2 "The Reef Aquarist" Hydroids. "These creatures are actually quite beautiful, and they are sometimes confused with soft corals because of their feathery polyps, brown colour and growth on stolon-like structures. These hydroids have a powerful sting that affects or kills neighboring stony and soft corals." I'll bring my book tonight since it has some decent pictures of what I had in my tank. Not saying this what is in yours.

[washowi]

I say they are sponges. My rocks are covered. (or they were).


Todd