[Sloth]

Whenever somebody brings up the issue of bristleworms, I maintain that there are different types of bristleworms. Those that will kill fish and those that will not.

My first tank had a HUGE worm that killed (I believe) and ate my only fish. It was over 6", was olive green or brown, shiney, segmented, and had "spikes" instead of bristles. It also had 5 antennae sticking straight out from its face.

On the other hand, all my subsequent tanks have had a healthy population of "regular" bristleworms. I've had them get at least 6" in length too, but NEVER harm a fish, snail, clams, or anything. These are the ones that are pink/white with a shiney blue/green sheen to them. Their bristles are more hair-like and stick like fiberglass in your fingers.

So that's my anecdotal answer. What did your worm look like?