Feather Duster Worms? Good or Bad?

This is not a pic of eactly what I have in my tank, but they are pretty close, except mine have a kind of stripe through them. They retract easy enough when something gets close.



Also, I have a good amount of this under my LR.



One question, these things are popping up everywhere and I want to know that if they are going to be a nuisance or not. If they are not, then I will let them be as long as they don't grow out of control. How big can they get?


Thanks in advance crew.

Kilted

They are safe and it's highly unlikely that they will grow to nuisance proportions. They are filter feeders, so if you keep your water quality high, that will control your populations. Hitch hiking feather dusters tend to stay small -- they don't get big like the ones you can buy at the LFS.

I've never seen feather dusters become a problem.
If you think their getting to be to many,most wrasses will will eat them.