Is this just a big Spirorbis tube worm?

Loring · Apr 1, 2022

Noticed this little guy hanging out this morning just curious if anyone has any idea what it might be?

DaJMasta · Apr 1, 2022

It's hard to see the shell in the image, but it could be something like. In my experience, they don't really get that big, so maybe some other type of filter feeder?

There are other fan worms that make tubes that may make ones with similar coils by chance rather than by default, or maybe some of the tube goes into the rock and only the top looks similar, but I think it's not your average feather duster... in fact, looking at the feather appendages, I would say not a normal feather duster (circular crown with visible feathering), and not a spirobid (again circular crown, but with a different look), and it looks much closer to the sort of single sided crown of a barnacle.

Loring · Apr 1, 2022

DaJMasta said:
It's hard to see the shell in the image, but it could be something like. In my experience, they don't really get that big, so maybe some other type of filter feeder?

There are other fan worms that make tubes that may make ones with similar coils by chance rather than by default, or maybe some of the tube goes into the rock and only the top looks similar, but I think it's not your average feather duster... in fact, looking at the feather appendages, I would say not a normal feather duster (circular crown with visible feathering), and not a spirobid (again circular crown, but with a different look), and it looks much closer to the sort of single sided crown of a barnacle.

hopefully the gif is working when you click on the image, but yeah I'm just not sure if I should greet my new tank make or cover it up w/ epoxy, been in a bit of a battle w/ hitchhikers lately from a piece of live rock I got to cycle my new tank from my LFS that turned out to be a grenade apparently.

DaJMasta · Apr 1, 2022

FWIW, very few of the things that I think I could be are invasive or dangerous to other things. Most filter feeders will just sit and do their thing and so long as they're extending far to irritate things, they can be largely left alone.