Those feather duster worms or copepods?

[Heidivee]

Put a bottle of copepods in the tank a month ago when I got my mandorin, tank is only 5 months old, wasn't advised of their food needs. Now I have these on rock and glass. Hoping their copepods but think the other.

 

[Clarkjw2002]

Spirobid worms. Kinda like a feather duster (which is also a worm).

 

[Heidivee]

Thank you.

 

[shakacuz]

+1 for spirorbid worm.