Small Tube growing on Rock

[Lindebrah]

Noticed this tube looking thing growing on my rock tonight after the lights turned on. I turned the lights on to take a picture and after a minute or two it receded and I could no longer see it. When I turned the lights back off it came back out. I haven't touched it but it looks soft. Thanks

 

[vetteguy53081]

Looks like a tube of a vermetid snail. These are highly undesired and should be removed.
Either break it off at the very base IR place a dab of gel superglue over the top of the opening

 

[Alexopora]

Noticed this tube looking thing growing on my rock tonight after the lights turned on. I turned the lights on to take a picture and after a minute or two it receded and I could no longer see it. When I turned the lights back off it came back out. I haven't touched it but it looks soft. Thanks

If you have a long turkey baster, you could just gently touch to see if its hard or soft. Idk why but it looks like a partially retracted lone zoa/palythoa or some kind of anemone. It looks way too thick to be a vermitid snail.