Hydroids all over my rock!

I have never seen them before in my 60g, I just switched tanks to a 40g and used all my old rock from the 60g. I can't get a good picture but here is one from google images. Are they harmful? How do I get rid of them? I heard peppermint shrimp eat them?

 

Normally these guys don't survive in our tanks. How large of an area do they cover? Can you pull the rock out?

 

No they are all over the place, the more I look, the more I find. theres a pretty good size colony on one main rock thats about 5inx5in and another 2inx2in colony on another. I did some reading and found out that they are temperate, my tank runs at 78.5 F, should I raise it to 80-82 to see if that has any effect?

 

Give it a shot, it won't hurt your other residents.

 

Ok will do, thanks for the help

 

I have some that are similar to this; they're just a little smaller and a bit more transparent. There's quite a few on some rocks, however they never been a problem for me. The corals near them don't seem bothered. Everything I've read says they'll eventually disappear, but they have been there about a year now. Never spread beyond the initial appearance.

 

Ok good, mine sound exactly how you described. I was just worried about my coral, but if they don't hurt them then I don't mind them