Random coral?

[D'sreef]

So these has popped up on a piece of live rock I got months ago from someone on FB marketplace. At first thought feather dusters or another tube worm, but now I am seeing branching. Anyone with any clue?

 

[IKD]

I believe they are hydroids but someone may have a better ID. I manually removed them with tweezers from my tank as they spread and bothered corals if memory serves. By the way, they may have a strong unpleasant odor when removed from the water.

 

[D'sreef]

I believe they are hydroids but someone may have a better ID. I manually removed them with tweezers from my tank as they spread and bothered corals if memory serves. By the way, they may have a strong unpleasant odor when removed from the water.

I don't believe that's the case as these have a skeleton structure, and is encrusting.