Coral Pest, Can't Find Any Info

[Dan I]

Hi, I just noticed that my hammer coral is dying from one side and noticed this black thin worm boring into it's base. I have a pulsating xenia, hammer coral, orange plating montipora, and a rose bubble tip. I dipped all corals with Revive before putting them in. When I noticed the worm I pulled out the coral and dipped it in Revive for 15 minutes. Placed it back in and noticed today it has a worm still. I was able to pull out 2 from it's base and noticed another worm near my montipora as if trying to go to it. Any ID or info to get rid of these pest? I'll try to get a picture soon.

 

[Dan I]

Here is a video of the worm in question. The worm is black and hair thin. Can't really see it here clearly, but I hope it's enough. Also, can this be moved to the Hitchiker and Pest forum. Didn't see that.

https://vid.me/EoQH