People are going to recommend bottle traps and pantyhose. These guys are so large that even if the worm goes into any trap, it will just back out. I believe that the worm doesn't completely come out of the lair, so trapping is nearly impossible. Watch the tank and try to figure out where it is living. If the worm is living in a rock, you can pull the rock and try to get the worm out of it.
@Dolphin2409 had luck with club soda and was able to remove the rock and the whole 36+ inch worm, his thread is in here somewhere. Mine was living in the sand bed and I had to break the tank down. The worm has probably been in your tank since it was set up. People think it should be easy to find one, but you first need to suspect the worm is in there. They are very adept at hiding and as you can see from your video, just how fast they are. They will pull large, heavy corals to their lair. I can keep corals alive now and the zoas are actually growing like they should. Don't lose sleep over the worm, I am still alive and have no battle scars from the freaking thing

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