First thing to note: These guys are bad guys… If you have one, you need to try and get it out of your tank.
Bristle worms are probably the most common reef tank critter, most aquarists will encounter them at some point in the hobby. Though most types of Bristleworms (Common Bristleworms) are fairly harmless, the Fireworm is a different story.
Fireworms are identifiable by their red colouration & their bristles are more “fluffy” looking in comparison to the Bobbit worm & common brislte worm.
Fireworms will actively hunt molluscs, crustaceans, invertebrates & corals. Larger worms have been known to prey on smaller fish too.
Fireworms can grow up to 24cm long, and often go unseen until the reach reasonable size. If you spot one in your tank, you should remove it as quickly as possible. This can be done with a set of tweezers or with a trap. You should not handle a bristle worm, the spikes they have will penetrate your skin and will likely be very uncomfortable.
Some aquarists will report that a bristle worm has eaten one of their fish, but it is likely that the fish was already dead or very sick. If they saw the worm snatch the fish, it is more likely to have been a Bobbit worm or a very predatory fireworm.
If you have clam, all bristle worms need to be removed from your tank, especially fireworms, their spikes can irritate the clams foot causing it to close up.
How do you control the numbers?
There are several ways of helping to keep your fireworm population in check.
Firstly, the more food there is available to them, the quicker they will reproduce, so cut back on your feeding if you feel you are getting lots of them.
Manual removal with a trap or tweezers is also advisable if you have a fireworm. You can find purpose built traps at several online vendors, or watch videos on YouTube on how to make a bristle worm trap.
You can also employ a predator for your tank. There are a number of species that will actively hunt all types bristle worms, though care should be taken that any new additions are compatible with your existing inhabitants.
Do they have any predators?
There are several fireworm predators. They include;
- Several Wrasse species are known to predate on bristle worms, including; Six Line Wrasse’s & Sunset Wrasses.
- Arrow Crabs, these are not generally considered reef safe though.
- Dottybacks, can become tank terrors,
- Hawkfish, will eat smaller fish & shrimps along with your bristle worm population
Not all of the species listed above are considered reef safe. Care should be taken when adding livestock to take care of a pest problem. Once they have eaten all of the pests, they will need supplementing with other foods, or they will need to be re-homed. It is for this reason that using a predator to take care of a pest problem, should be your last resort.