fire worm

Question
A friend on ours gave my son a 10 gallon saltwater tank that was already up and running for sometime before we got it. We have notice a very big worm that looks like what is called a fire or bristle worm. This worm has what looks like white spikes on the side of its body. It is a dark grey or purple color in the middle but it greyist white color over most of its body. We have not seen the whole worm so not sure of the size. Only seen about 8 to 10 inches of it. Most of the local fish stores tell me to get rid of it that it is not go for our tank?

Answer
Hi Shawn. Some fire worms can be very harmful to corals in a saltwater tank. Most however are beneficial scavengers. The ones that are harmful are very rare to see in an aquarium and almost never hitch hike on live rock. Before you do anything drastic try to find out exactly what species of fireworm you have. Even if it turns out to be of the bad variety they do not prey on healthy fish only corals and some anemones. Unless you have any of those in there a large bristle worm can be a very interesting inhabitant of a fish only marine aquarium. The dangerous one is called a Coral Eating Fireworm(bearded fireworm) scientific name; Hermidice carunculata. Google these names so you can see if yours matches. If it does you may want to set a trap for it using pvc pipe capped at both ends with small holes in both caps. Load the trap with a piece of bait(clam, mussel, squid etc.) and place it in the bottom of your tank before the lights go out. Check in the morning and reset up with fresh bait the next night. Keep doing this until you have caught him. Do not touch him. The bristles are venomous and can cause a very itchy and painful rash.