Fan worms ?

[JackPinny]

Are these fan worms or feather dusters

 

[tbrown]

Looks like micro feather dusters. Harmless. They typically explode in population numbers in a newer tank and then migrate to the dark areas in the back of the tank or the sump.

 

[ISpeakForTheSeas]

To my knowledge, fan worms and feather dusters refer to the same category of worms (taxonomic Family Sabellidae), so yes, they are fan worms/feather dusters (though one term or the other may be applied specifically to the common names of certain species in the family).

As mentioned above, they’re harmless filter feeders.

 

[EeyoreIsMySpiritAnimal]

feather dusters are fan worms

So, yes