Weird growth on my rocks.

[JammyBirch]

I have these very small polyp looking things on a few of my rocks, they have a stem or base all of them have brown bases most of them have brown polyps some of them have green polyps.

First of all they are tiny, have been in the tank since I added the rock, ~ 3 months, and have not gotten any bigger or increased in number.

At first I was thinking aiptasia and I've been looking all over the net to be sure...

I haven't found anything that looks like this, I'm probably not using the correct search words because I don't know what it is.

Anyone have any ideas...? I tried to take some pics but they are not of good quality.

 

[zeebies]

Colonial hydroids come in green and brown.

 

[JammyBirch]

That's what I got...thanks I'd have never figured that out.

Since they are not going nuts do I need to remove them?

 

[zeebies]

If you overfeed or give them a lot of light, they can really spread. They can also give quite a sting, I hear. If they're in a low light, low flow area, you might be ok with letting them be, but...

I had a couple of little patches. I took the infected rock out and chiselled out a good chunk of rock underneath the hydroids and took out the droids with the rock. They've never reappeared in my tank. If you can't move the rock, some people have success with smothering them in epoxy.

 

[wcarterh]

Possibly hydroids. A photo would help if you can manage one with decent quality (can be hard with tanks).

Kalk paste or Blunt-End Sea Hare" (Dolabella Auricularia) if hydroids.