What is this?

[matthappe]

I noticed this yellow tube growing out of a dead looking tube in my tank. It is very hard and i noticed it about 2 weeks after setting up my FOWLR tank. What is it?

 

[Beengirl]

Could be a feather duster. Does anything ever come out of it?

 

[matthappe]

I haven't seen anything come out of it yet and i have checked at night and still saw nothing

 

[Flreefer]

It's a Spirorbid worm tube, harmless.