Welcomed guest or pest?

[isis.aphrodite.]

I just set up my saltwater tank about 3 months ago and now I have found what I thought may have been nudibranchs but now I'm not so sure. If they are great...if their not what are they and will they cause problems?

 

[isis.aphrodite.]

The other one

 

[scooter31707]

looks like Bristleworms

 

[Sugar Magnolia]

looks like Bristleworms

Yep, bristleworms, a beneficial part of the clean up crew.

 

[GimpyFin]

+1, bristleworms. They are a common hitch hiker and for the most part, a good scavenger/cleaner for your tank.

 

[isis.aphrodite.]

Thank you