Tips on Keeping the Red-Toothed Triggerfish

Click image to enlarge Red-toothed triggerfish are not hard to feed. They will eat any type of meaty food you toss in the tank. Photo credit: Al Castro

Among triggerfish species, there is somewhat of a ragged divide between those "most likely to bite" their tankmates (and quite likely you) and species toward the more mellow end of the spectrum. The "more likely to bite" group would definitely include the clown (Balistoides conspicillum), titan (B. viridescens) and queen triggerfish  (Balistes vetula). Calmer species include the more commonly available Sufflamen species and lagoon triggers (Rhinecanthus species). Another trigger that will play nice in your tank is the monotypic Odonus. This fish, the red-toothed or Niger trigger (Odonus niger), can be an easygoing beauty - it is not a chewing monster that will bother other animals in your system.

The red-toothed trigger gets its common name from the color around the mouth that develops as the fish attains maximum size (to 18 inches). There is a considerable degree of color difference across this fish's natural range (throughout the Indo-Pacific, including the Red Sea), and its color varies depending on the fish's mood, food, feeding and water quality. It is the only Odonus species, and there are no discernible structural (morphological) or color differences between the sexes. Some specimens don't develop the externalized red teeth that give them their common name, but most do, given time to mature and the proper diet.

Selection
Picking out a healthy Odonus triggerfish is a simple task. Almost any that are outgoing and that are observed to be feeding will "make it" in your system. Don't be dissuaded by torn or shortened fins, or other apparent blemishes. This species is tough and heals quite quickly.
If you go the quarantine route to discount the introduction of pathogens and parasites, include a bit of large-diameter PVC pipe or fittings for your trigger to hide in while in the quarantine tank.

The Odonus Aquarium
Odonus niger needs room to move, grow and feel safe. You may get by with a small individual (I've seen them sold at less than an inch long) in a system of tens of gallons, but if you intend to keep one in good health for the long term, a minimum of 125 gallons is recommended (twice that volume is better).

With such large and active fish, good circulation, aeration and filtration are requisite, as well. Practically speaking, there can't be too much water movement, with a minimum 10 turnovers per hour, an oversized protein skimmer and oxygen-saturated water conditions being required. I encourage you to not use the "traditional" approach with rock (layering of solid decor) along the back of the system. Instead provide free-standing "bommies" with holes that the fish can pass through. Such arrangements will facilitate complete water movement and give your trigger (and other fish) opportunities to hide out of the visual way of each other and you.

Tankmates
Name a potential tankmate and an Odonus may try to eat it. It is possible that a red-toothed trigger may eat slow-moving fish, large fish and any type of sessile invertebrate (including corals). This being stated, some folks have kept red-toothed triggers with nearly everything with impunity, and there are some ways to stack the odds more in your favor.

First off, start with a smaller specimen that is a few inches long. Larger specimens are often "set in their ways" and know just how tasty other elements of your tank can be. Feeding the initially small specimen with nonlive foods, particularly dried prepared or mashed frozen varieties, helps keep them in the dark regarding how tasty their tankmates are.

Reduce territoriality and its possible dire consequences by making your trigger the last addition to the tank. It is best to give them large quarters with many gallons in which to cruise around. Also, stock your tank well, as including many other animals will go a long way to diffuse predation. As far as picking on or outcompeting slower fish, such as lionfish and eels, Odonus is about the safest member of the family to try. Clams and small crustaceans (e.g., shrimp and hermits) are likely to get munched. However, in most cases, Odonus will leave corals and their relatives alone.

Can you keep more than one Odonus specimen in a given tank? Yes, Odonus is likely the most social species of the Balistidae family and is found in large associations in the wild. It is better to have small, odd numbers rather than a couple. If you have room for three or more, they will get along fine. On the other hand, I would not place this more peaceful balistid with other triggerfish species, as there is too great a likelihood for fighting.

Disease
As with all triggerfishes, Odonus is tough and generally resistant to all but the most virulent cases of parasitic disease. It will usually be the last to succumb to many sources of mortality (poor water conditions, a lack of food, etc.). If your system itself becomes infested, balistids respond well to conventional copper therapies.

Odonus Feeding
The red-toothed trigger is mostly planktivorous in the wild, feeding on small animal life that is borne by currents in and about areas of upwelling. In captivity, though, this fish will gladly accept all types of meaty foods, with bivalves, crustaceans and worms of all sorts being preferred. An inexpensive adjunct to their keeping is the purchase of mixed frozen seafood that you can get in many food markets. There is no need to shell this seafood - simply defrost and toss it in.

Providing a system of size with plenty of hiding spaces, starting the specimen small, avoiding live food - and above all, constant vigilance - are the steps to success in keeping Odonus niger in captivity along with your other livestock. This fish can be a great joy, even a centerpiece of a good-sized reef system (if given room and conditioning, Odonus can be reef-safe). The onus is upon you, should you choose to try and keep this species. Keep your eye on it. FAMA