Bristleworms.. good..bad?


New member
last week i found mini brittle starfish on my live rock. and then i saw a bristle worm peak out for a moment then hid back underneath the rock. I just talked to my friend that has some experience with sw tanks and told him i saw a bristleworm.. he said those are bad and ill want to get it out of there.. but last week when i posted on here, most people said they were good. now im confused what to do.. even if i do have to take it out.. i only saw it that one time last week..
are they good... are they bad???
Some people will say they are bad because if something is dead in the tank they are usually seen all over that said dead thing. I think they are good unless they get to big i.e.

But they do play a integral part of the "cleaning" in your tank taking care of uneaten food and such. I would leave them in your tank until they pose a problem.
In the southern US, where many specimens come from the Caribbean Sea, they come infested with a type of bristleworm that is smaller, darker, and meaner than the Pacific bristleworm---the Caribbean variety can kill corals and deliver a nasty sting. The Pacific, often quite large, pale, often looking a lot like a brittle star arm, is harmless to corals, and often brushes by them with no harm at all. They are detritus feeders. If you have had experience of the southern worms, like me, you tend to twitch a bit at the mere sight of them, envisioning death and destruction, but living up north where specimens come in from the other ocean, I've made my peace with the large sort and admit they're assets to the tank.
get some warasse when you don't want to see them no more down the road. I used to see alot of them in my tank a few yrs back, but now I hardly see any 'cause I have 5 wrasses in my tank
Bristle worms are good. They eat waste left behind by others and are an important part of your tanks eco system and clean up crew.
Bristle worms are good. They eat waste left behind by others and extra food. Plus their numbers grow and shrink quite nicely with your tank's bioload.