I.D. This, Good or Bad

Are these something I should concerned with. I have no idea what they could be.

 

Colonial hydroids.

They can (and will) overtake anything/everything if left unchecked.

 

And they can sting and harm corals

 

very hard to get rid of, I would like to hear how to rid them?

 

Thanks for the quick reply.What would you suggest to prevent a takeover or any other problems they create and also what helps them grow to the point of a takeover ?

 

I've has the same quarter sized spot of these for a year, I'd also like to see about removal. They haven't hurt anything thus far.

 

I've got some also that's been staying still for a few months. But since I don't have Kalk paste I might just yank the rock out for a bit. I got aiptasia on a other rock near them on the bottom so it might be time to do a lil scaping. I got some aiptasia x. I wonder if it would kill the hydroids? I might try this tonight before pulling rock.

 

I had a small patch of colonial hydroids that stayed quite small and didn't spread for a couple of months, but found out the hard way that when phosphate, nitrate or both spike, they start to takeover.... really fast!
So basically, high nitrates and/or phosphates help them thrive. As they haven't gotten too out of control yet, I haven't given up on finding a way to get rid of them. But so far, I can't find a suitable removal method that doesn't involve taking out the rock. I'll tag along on this thread because I'm also interested in how to get rid of them.

 

It's funny, I've had mine for 3 years+ and it's never grown either.

Areas that are small enough can be covered with epoxy. You just touch them so they pull in and then cover them up.

 

I had a small patch that never seemed to grow but to be safe I ended up pulling that rock out.