ID Help

[Ian Baxter]

I’m trying to figure out what these are so I can create a good plan of action to get rid of them. I have taken the large rock out, soaked in peroxide for about 10 minutes, scrubbed and rinsed it clean and everything came back. I also have it growing on the sand. I think it’s either sarcothelia or colonial hydroids but I don’t know a way to tell them apart

 

[Decamicron Labs Verified Sponsor]

Definitely not colonial hydroids. It is some octocoral, however, I wouldn't be comfortable assigning a genus name until one could look at sclerites from an expert at least.

 

[Tahoe61]

Dreaded clove polyps.
https://www.reef2reef.com/threads/remove-clove-polyps-for-good.967400/