Yeah, it's a big guy. I was thinking of a longer bottle or a length of pvc with caps on either end. I have read (what I can find) is that a lot of these are detrivores and people have them for years without ever noticing until a tank breakdown. Most of what I have read has worms like this listed as a Bobbit, but others note that there are many types of worms in this family. I need to figure out a way to get a video at night to try to get an identification, I can't get close enough to get a picture, he is always observant and very quick. I have had corals damaged, but since moving the filefish, I have only had corals moved. Worst case, I break down the tank and get him out and maybe get him rehomed, I hate to kill something just because he is big and ugly. Heck, they let me live this long...

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