Bad bristle worms?

[MMM33732]

I hear people freaking out about bristle worms in their tanks from time to time. I always understood that they were beneficial. Why would some say they are bad?

[Don-Coraleone]

they could be a prooblem if there was an out break in the tank but other wise i thought they were good for your tank.

[MMM33732]

So you think some people think they are bad because they can multiply fast?

[greenbean36191]

There are two major reasons.

1. People can't identify worms worth a flip. Most hobbyists call any worm they see a bristleworm without any attempt to identify it further. You get lots of worms lumped together that have very different behavior. You can have one guy talking about a harmless fireworm and another talking about an 8 ft long eunicid as if they were the same animals.

2. Most of the bristleworms in the hobby are quite fond of dead things. Since many "simpler" animals are very limited in their ability to show that they're unhealthy (and it's not very adaptive to advertise that anyway) they often seem to die without having ever showed any signs of ill health. Who do we find at the scene?... the bristleworms. The (false) assumption is often made that since the animal appeared healthy, and now it's dead and covered in worms, they must have caused it.