Triggerfish :
This column will give an overview of several of the beautiful species of the Family Balistidae, more commonly known as the triggerfishes. They are hardy fish that will typically eat whatever you try to feed them, and will usually have more personality than any other fish in the tank. On the downside, they can be aggressive towards other fish, might re-arrange the rockwork, and may nip at both your corals and your hands. The biggest obstacle to writing an article about Balistids is that they defy generalization. There is a wide variation of needs and personalities across the genera; even within a species there can be tremendous differences in individual fishes.
Family Balistidae :
The Balistidae consist of approximately forty species in eleven genera. About half of these make it into the aquarium trade. Triggerfish have a deep-bodied, laterally compressed design with large, non-overlapping scales. Some species have forward curving spines on the posterior portions of their bodies that can be used for fighting.
The first dorsal fin is made up of three spines and can be depressed into a groove on the fish's back. When erect, this spine can be locked into place by the second dorsal fin, known as the "trigger" spine (from which these fish derive their common name). When threatened or sleeping, triggerfish will wedge themselves into a cave or hole in the rockwork, erect the first dorsal spine, and lock it into place with the trigger spine. This makes them extremely difficult to extract by would-be predators. The soft fin rays are all branched, and there are no pelvic fins. The dorsal fins have 24 to 36 soft rays and the anal fins have 19 to 31 soft rays. Balistids have eyes that are set far from their mouths, and serve as protection from the claws and spines of typical prey such as crustaceans. They have small mouths, with fused jawbones and strong teeth designed for breaking up coral and rocks and crushing hard shells.
Note the teeth and powerful jaws in this Balistoides viridescens, the Titan triggerfish. They may grow to over 2 1/2 feet, making it too large for most home aquaria.
In the Home Aquarium:
Balistids have many attributes that make them a great fish for the marine aquarium. They are robust, eat a wide variety of foods, and many of them are quite beautiful. The downside is that many have aggressive and destructive natures, making them less than ideal for a community or reef tank. Of course, there is wide variation between, and even within, the different species. I have found that the larger the tank, the less trouble there will be with destruction and aggression.
Triggerfish should be kept in a tank that is large enough to give them plenty of open swimming space. They should also be provided with rockwork containing holes where they can lodge themselves when feeling threatened by either the aquarist or larger aggressive fishes (such as Acanthurus sohal).
Feeding is easy with this family. Balistids will usually eat any food offered to them. They should be given a varied diet of meat and vegetable matter. It is important to include some hard-shelled foods to help them wear down their continuously growing teeth. Shrimp, squid, clams, marine algae, and fish are all good choices of readily available foods. Feeding live foods should be avoided, since it will increase the chances that your fish will be aggressive towards the other animals in your tank.
Selecting a triggerfish is fairly straightforward. While not particularly resistant to common aquarium diseases such as Cryptocaryon irritans, they do seem to recover more quickly than most fishes and can tolerate all of the widely used remedies. Unfortunately, they are often used to "cycle" new aquaria. This practice should not be done with any fish. There are too many other ways to cycle a tank without risking the death of a fish. If triggerfish are the first fish added to the tank, they may defend the entire tank as their territory, and can make it difficult to later add other fish.
Finding good tankmates for triggerfish can be very difficult, and an aquarist needs to think about this ahead of time. Triggers with "up-turned" mouths (Xanthichthys, Melichthys, Odonus) tend to feed more on zooplankton, and are typically less likely to bother corals and small fishes. These fish can usually be kept with large peaceful fish, smaller, aggressive fishes (such as dottybacks), and more aggressive dwarf angels. They may attack small peaceful fishes, especially zooplanktivores that stay in the water column, such as chromis and small cardinals. In summary, to maximize coexistence with other fish, triggerfish should be kept in large tanks, fed well, and put into the tank last.
If you intend to keep ornamental crustaceans such as cleaner shrimp, it is better to stick with the zooplanktivorous triggers, which will be less likely to attack. Putting the crustaceans into the tank first will maximize the chances of their coexistence. Be sure to approach owning a triggerfish with the understanding that you may lose some shrimp along the way.
Maintaining a clean-up crew in a triggerfish tank can be difficult. Triggerfish's jaws are designed to bite through the shells of snails and hermit crabs. They will also flip the animals onto their backs and enjoy an easy snack. Again, triggers with up-turned mouths are less likely to eat shelled organisms, but may still do it at times. Many hermit crabs will hide during the day, and only move around the rocks at night. With the larger, more aggressive triggers, the tank owner will most likely replace the clean-up crew because of the losses incurred. When cleaning the tank, always keep an eye on the trigger and consider wearing thick gloves, as many of them can (and will) deliver a large, painful bite.
Triggerfish are often selected for fish-only tanks with aggressive inhabitants, which suits many of them well. Lionfish are also commonly used for tanks housing aggressive fish. This unfortunate pairing often leads to the demise of the lionfish. Triggerfish are experts at avoiding the venomous spines on lionfishes, and are able to attack and kill lionfish, avoiding the spines without being stung.Rhinecanthus triggers are especially common culprits of lionfish mortalities. Those with upturned mouths, being more peaceable, are less likely to engage in such behavior.
Part of the appeal of many of the Balistids comes from their unusual behaviors and antics. Of course, this can also be considered part of their downside in the home aquarium. One such behavior involves rearranging rockwork in the tank. In the wild, triggers will move and break pieces of rock and coral to find food, such as urchins and crustaceans. While this behavior can be fun to watch, it becomes much less endearing when a trigger flips over or drops a piece of rock on top of that prized coral. In an attempt to alleviate this problematic behavior, many aquarists will leave small "toys" around the tank for triggers to move. Rhinecanthus spp, Pseudoblastes fuscus, and Balistes vetula are the most common culprits of this redecorating behavior, though any triggerfish may do it from time to time.
Triggerfish will often lie on their side above the substrate and undulate their dorsal and anal fins, sending up a cloud of sand, detritus, and microfauna. This is another feeding behavior that allows them to expose buried animals, and they will swim through the cloud of debris picking out small benthic organisms that were flung into the water column. A downside to this behavior is that it makes many triggerfishes incompatible with tanks containing a deep sand bed. Xanthichthys and Melichthystriggerfishes are less likely to do this.
Spitting is another common triggerfish behavior. This is an adaptation of their natural feeding behavior. In the wild triggerfish will hunt by hydraulic jetting: they blow water out of their mouths and into the sand to uncover prey. In the aquarium, they learn to associate the surface of the water as the best source of food rather than the substrate, so they go to the surface for jetting. This habit can be a hazard if the tank is uncovered and there are electrical outlets or power strips near the tank.
Common Triggerfish Species:
Xanthichthys auromarginatus, commonly called the blue-chin or gilded triggerfish is found in the Indo-Pacific at depths from 25 to 500 feet. It feeds on zooplankton, growing to about one foot in length. The species is sexually dimorphic, with females lacking yellow margins on the tail and anal fins, as well as the blue chin that gives the male fish their common name. This species is the most common Xanthichthys trigger found in the aquarium trade, and is occasionally found available in mated pairs. It should be housed in a larger tank that will give it plenty of swimming space.Xanthichthys auromarginatus individuals are less likely than individuals of many other triggerfish species to pick at sessile invertebrates.
Xanthichthys mento, the crosshatch trigger.
A close relative of Xanthichthys auromarginatus, X. mento, the crosshatch trigger, will form schools on the seaward side of reefs above drop-offs. The crosshatch is found in the Eastern and Western Pacific Oceans, at depths of 10 feet to 330 feet. This fish is sexually dimorphic. Each scale is outlined in black, creating the "crosshatch" look. Males have a yellow color and a red tail with a blue submarginal band. In females, the scales and tail are gray to blue. In supermales, each yellow scale has a light blue dot in the center. This open ocean fish grows to about a foot in length. The crosshatch trigger is peaceful, but, like X. auromarginatus, should only be put into a tank that will give it a lot of open swimming space. Feeding and tankmate requirements are similar to X. auromarginatus. Unfortunately, this fish does not do as well in aquariums as most triggerfishes. For unknown reasons, it has a tendency to develop an abscess or tumor in its mouth, which stops it from eating.
Melichthys niger, often called the Black or Durgeon triggerfish, is a species with circumtropical distribution, and is found from the surface to depths of about 250 feet. These fish can be found in small groups, commonly on the seaward side of reefs, and grow to about 20 inches. Those sold in the United States are usually from Hawaii. The diet of M. niger consists mainly of floating fragments of macroalgae and fish feces. They will also eat some zooplankton. These fish are very peaceful by triggerfish standards, and usually leave other fish and sessile invertebrates alone. However, they may attack small, peaceful fishes and ornamental crustaceans. Melichthys niger should be given a diet fairly heavy in vegetable and plant materials, with some meaty foods.
The pink-tail trigger, Melichthys vidua, is probably the triggerfish most commonly kept in reef aquariums. This zooplankton feeder is found throughout the Indo-Pacific at depths from about 13 feet to 200 feet, and grows to about 16 inches in length. It feeds on detritus, macroalgae, benthic crustaceans, and sponges. This fish can range in color from a dark green-gray to a light olive color, and the tail can range from almost white to a dark pink. Like M. niger, this fish should be given a diet that is heavier in plant material. It will typically ignore most sessile invertebrates, but may attack ornamental shrimps and may eat sponges. This triggerfish is less likely than many other species to rearrange the tank décor. Melichthys vidua can be kept with peaceful fish its size, or with smaller, more aggressive fish. It is a popular triggerfish for reef tanks because it is smaller than M. niger and more common (and so, less expensive) than the Xanthichthys triggers.
The triggerfish with the personality that is most difficult to predict is Odonus niger, the Niger or Red-toothed trigger. Although sometimes called the Red-toothed trigger, not all individuals will have red teeth. Odonus niger is found on Indo-Pacific reefs at depths from 16 feet to about 130 feet and grows to about 20 inches. It feeds mainly on zooplankton and sponges. This species will form large aggregations.
Odonus niger will usually leave corals alone, but will often nip at tunicates, sponges, and snails. Some individuals will be the "baby" of the tank, being easily bullied by any other fish. At the other end of the spectrum are Nigers that will not tolerate the presence of any other animal. To successfully keep one of these in a reef tank, it is best to "test" its behavior in another tank. Put the fish in a smaller tank with less structure than you would typically have in a reef tank. Some aquarists do this in their quarantine tanks or in fish only systems with minimal rockwork. This way, if it is a terror, the whole display tank will not have to be torn down to get it out. Of course, even this won't guarantee that it will not cause trouble once it is in an aquarium, but it will minimize the possibility. The larger the tank, the less likely this fish will be to cause damage to tankmates and to the décor. There is also a lighter gray color variation found around Sumatra called the "Cobalt" Niger, which is reported to be more peaceful and slightly smaller in size.
Odonus niger
Triggerfishes in the genus Rhinecanthus can be discussed as a group, since they have similar physical and personality traits. There are seven species in this genus, including the Picasso trigger (R. aculeatus), the Assassi trigger (R. assassi), the Rectangulated trigger (R. rectangulus), and the Blackbelly or Bursa (R. verrucosus) trigger. Several of the fishes go by their common names, Picasso and Huma (or Huma Huma). Found in the Indo-Pacific, they are typically less than a foot in length. In the aquarium, the Rhinecanthus triggers are peaceful as juveniles, and may initially make good community aquarium fish. However, as they grow, they tend to become more aggressive. They may eat nearly any motile or sessile invertebrate, with the exception of large cnidarians with powerful stings. They eat a wide range of foods, and will take almost any plant or animal matter offered. These fish will also rearrange rockwork, and may bite heaters, power cords, and filters. Rhinecanthus triggerfish are especially bad tankmates for lionfish, as they are even more prone than other triggers to pick at the lionfish's spines. One nice aspect is that the fish in this genus have more personality than almost any other fish available for aquariums.
Rhinecanthus aculeatus, the Picasso trigger.
Balistapus undulatus, or the Undulated trigger, is a gorgeous fish, and it is one of the most predictable triggers available. They grow to about one foot long, and they are found in the Indo-Pacific and Red Sea at depths from about 5 feet to about 165 feet. They feed on a wide variety of benthic plant and animal organisms. These fish are highly territorial; especially females after eggs have been laid.Balistapus undulatus is a sexually dimorphic animal; the males lack orange lines on top of the snout. These fish cannot be housed in a reef aquarium. They will eat just about anything, moving or not, and are willing to attack and kill anything that cannot kill them. If they are to be kept with other fish, it should be in a large tank with only large, very aggressive tankmates. There are some reports that Red Sea Undulated triggers are slightly less belligerent.
The Clown trigger, Balistoides conspicillum, is one of the most easily recognized fish. The white spots on its belly and yellow dorsal markings are very clear. It is found in the Indo-Pacific at depths to about 250 feet, and can grow to approximately 20 inches. Balistoides conspicillum eats a wide variety of benthic organisms, mainly meaty animals.
Balistoides conspicillum, the Clown trigger.
Balistoides conspicillum can be housed in a community tank when young, but it can become very aggressive as it grows. Many aquarists are able to keep Clown triggers with more peaceful fish for years, only to discover that their fish takes on a nasty personality almost overnight, often killing everything else in the tank. These fish grow very quickly, and there is no predictable size where the personality change occurs. They are not suitable for the reef tank. Tiny Clown triggers, which are commonly collected, have a very high mortality rate. These fish are often a fraction of the usual price of Clown triggers, and have an even higher mortality rate.
Pseudobalistes fuscus, the Blue-lined trigger.
Pseudobalistes fuscus, the Blue-lined (or Yellow-spotted) triggerfish is found from the Western Indo-Pacific to the Great Barrier Reef at depths to 165 feet. It is uncommon in the Eastern Pacific, and grows to about 22 inches. It feeds on benthic organisms, tunicates, corals, fish carcasses, and crustaceans. Juveniles have dark saddle spots and blue-grey spots. As the fish ages, the blue spots grow and connect, creating the blue-lined style of the adults. This trigger is not as aggressive as the queen or undulated triggers, but it is a very aggressive fish, and is large enough to do more damage than B. undulatus. Juvenile P. fuscus can be kept in community tanks, but sub-adult and adult animals should be housed only in a very large aquarium, and kept only with other large aggressive animals. It will typically attack fish that come too near to them when feeding. It will eat most invertebrates, motile or sessile. This triggerfish is also the most likely to rearrange rockwork. It is able to move very large pieces, and even break apart pieces that are glued together.
Balistes vetula, the queen triggerfish.
The Queen triggerfish, Balistes vetula, is another beauty with an aggressive streak. This is the largest of the triggerfish commonly available for aquariums, growing to about 2 feet. The Queen is found in the tropical Atlantic at depths from 6 feet to 900 feet and feeds on benthic invertebrates, motile and sessile. While not quite as aggressive as Balistapus undulatus, but at twice the size, this fish is a real danger to corals, motile invertebrates, and other fish. Unless kept in an extra large aquarium, this fish is best left on its own (or in the ocean). Even in tanks as large as 500 gallons, there is a reasonable chance that B. vetula will kill all its tankmates. It will rearrange all of the aquarium décor, and it is not unheard of for this fish to shatter heater tubes and bite through power cords.
Summary :
As with any marine aquarium fish, the key to successfully keeping a triggerfish is to do your homework beforehand. The right triggerfish can be a great addition of color and personality to your aquarium, provided you go in fully aware of their potential pitfalls. If you want to keep a trigger in a reef tank, you should stick with the triggers with the “up-turned” mouths: Xanthichthys, Melichthys, and sometimes Odonus. If you just want a large, beautiful fish, and do not mind the tankmate limitations, then the other triggerfishes are great pets.
Triggerfish :
courtesy to : www.advanced aquarist . com By Jim McDavid
Triggerfish are highly resilient animals, and for the most part they ship well and feed from the time they are collected to the time they make it into your home aquarium.
Many aquarists, both freshwater and marine alike, first become interested in this hobby by simply deciding one day, for one reason or another (maybe after seeing a friend’s tank) that they would like a fish tank in their living room. Then, (hopefully) some research begins, and at some point during the many trips to the fish store and hours spent reading every article and book available, the new hobbyist decides on what fish he wishes to populate his newly set up tank with. A particular favorite or two may emerge, and if the aquarist is lucky, these are hardy, compatible, easily obtained species.
Others like myself, were seduced into the hobby by a single particular fish, and all thoughts and actions surrounding and leading to obtaining that magical glass box centered on the needs of this one fish. Obsession follows, and all the research and purchases are made to accommodate this must have animal. The origin of my involvement in the marine fish hobby over two decades ago falls into the latter category. The fish, or rather group of fish that so irreversibly pulled me in were the members of the family Balistidae – more commonly known as the Trigger fishes. In the years since, I’ve expanded my interests and have kept representatives of just about any family you can name, but if I could keep only a single fish in a single tank, it would undoubtedly be a Triggerfish.
What exactly is a Triggerfish?
Not your average aquarium denizen for sure. Let’s take a look at what makes them so unique.
Triggers belong to the order Tetradontiformes “four-tooth bearing”, and the family Balistidae, and are closely related to 9 other families, including among others, cowfishes, filefishes, puffers and leatherjackets. Most species in the order, and certainly all the members of the family balistidae practice balistiform locomotion (using the dorsal and anal fin rather than the caudal fin) almost exclusively, although the caudal fin is sometimes used for short bursts of speed. In simple terms, these fish do not normally use their tail for swimming, but instead undulate their dorsal and anal fins, keeping the body rigid. This gives the effect of a small hovercraft moving about, and is part of what endears the fish to so many hobbyists.
The Balistoids are laterally compressed, generally rhomboid shaped fishes, although a few species are slightly elongated. They have a non-protrusible upper jaw, with hard, specialized teeth that in most species are designed for cracking the shells of various hard-shelled invertebrates. They have independently rotating eyes, and their pelvic fins are fused into a single spine. They have two dorsal fins, the first of which is comprised of three spines, and this is where the Triggerfish derives its name. They can use this spine, along with the ventral spine to lock themselves into coral heads or rock crevices when threatened, and once they do, they are immovable!
From an evolutionary standpoint, triggerfish are some of the most advanced fish in the sea. They are heavily armored, intelligent hunter-killers of the reef, and have a set of jaws that can annihilate any hard-shelled invertebrate you care to name They can also destroy just about anything else you care to name, both alive and otherwise, but we’ll get to that shortly.
Interesting, but why would I want one?
For starters, as with other members of the order, Triggers are atypical to say the least in the morphology department. A vast majority of fishes seen by both freshwater and marine hobbyists belong to the order Perciformes, or “perch like” to use the common term. While we can get technical again, it will suffice to say that all these fish share certain morphological characteristics that cause them on the whole to look more the same than they do different. You may have a Clownfish, Angelfish, a Surgeonfish and a Dottyback residing in your tank, and while they are seemingly quite dissimilar, they’re really quite close in morphology and are for the most part variations on a theme. Fish of the order Tetradontiformes however are strikingly different than their cousins in the order Perciformes, there is just nothing else in the ocean like them. They almost give an impression of some sort of alien craft maneuvering here and there rather than fish. .In this assemblage of very unusual and interesting fishes, the Triggers are the most suitable for aquarium life for a variety of reasons. While some notable exceptions exist, the equally stunning, intelligent and bizarre fishes belonging to the other families in the order are often either very delicate, notoriously disease prone, (internal and external parasites) poor feeders in captivity, or exude toxins that can wipe out an entire tank. Some will even provide you with a combination of these traits! Fortunately, the Triggerfish share none of the above problems with their other relatives in the order.
Aside from their unique morphology, the next thing that will grab your attention about a Triggerfish is the color. A few species are like living, breathing modern art paintings, and the Picasso Triggerfish in particular looks like something out of a children’s story, almost too fanciful to be real…but there it is! A few species are just out and out garish, while some have a more subtle beauty.
Picasso Triggerfish
One of the other striking qualities about the family as a whole is the obvious intelligence exhibited by these fish. Triggers are very deliberate in the way they go about their business, and don’t move about in a seemingly mindless or programmed fashion exhibited by some other genera. You can almost see the gears turning as they examine their surroundings, or maybe contemplate a possible food item or a newly introduced object or inhabitant in their environment - eyes rotating like some advanced sensor al the while. As with freshwater fish of the family cichidae, they can learn to recognize their keepers, and further, what behavior by their human keeper usually results in a treat being introduced into their home.
Are you convinced yet? How about this - they are hardy…no, indestructible! Well, that might be overstating things a bit, but let’s just say that if you can’t maintain a Triggerfish in a healthy, thriving state, you best turn in your glass box and go get a pet rock, because that’s about the only thing tougher than one of these fish. They are as forgiving as aquarium fish get, and not even amongst their commonly kept freshwater relatives can you find a more resilient fish. Among other things, this of course means that they are tremendously disease resistant. This quality alone should automatically endear them to most potential owners immediately. They rarely succumb to the common marine parasites that rear their head now and then in captive systems, and in over 20 years of keeping marine fish, (including the early days when my husbandry practices were not so careful as they are now) this author has never lost a Triggerfish to any marine fish disease. On the rare occasion that a Triggerfish does become infected with a parasite such as Cryptocaryonirritans (saltwater ick) they recover with just a bit of TLC on the part or the aquarist. If that doesn’t convince you, back in the day when cycling a new tank with live fish was the norm, I used Triggers of the genus Rhinecanthus on more than one occasion instead of the more normal damsel fish for this task. I’m not advocating this practice of course, this was many years ago, and we’ve moved away from even using Damsels to cycle new tanks. It should nevertheless be a fairly good indication of the inherent hardiness of the family as a whole. Having said this, there are Trigger species that while still hardy by most standards, would not fare so well under such treatment.
What else do I need to know?
Plenty! Let’s begin with choosing a suitable tank: The tank you will need to house your Triggerfish depends on the species you plan to keep, and what you plan on keeping it with. Some Triggers always end up alone, or traded back to the fish store, regardless of the extent to which they tolerate tank mates when young, so the aspiring trigger keeper needs to keep this in mind when selecting the species to be kept. Others will live out their lives in a community setting with few problems provided enough space is provided, some stocking order rules are honored, and tank mates are chosen with some care. A few will even live in a reef setting. In any case, tall narrow tanks should be avoided, as these are very active animals, and need as much swimming space as can be provided. A hexagonal tank is a very poor choice for a trigger unless it happens to be a very large one.
Undulated Triggerfish (Balistapus undulatus)
As is the case with many families, a wide gamut of adult sizes, growth rates and temperaments makes generalizations difficult with regard to the minimum tank size. Further complicating the matter is the fact that even though a given species may attain say 14” in the wild, this doesn’t necessarily mean that such a size is realistic in captivity, even when kept in the largest home aquaria. Others are just tremendously slow growers, and are not likely to reach anything close to adult size even after 6 or 7 years of captive life. A good example of this is the genus Rhinecanthus, which comprises a few very popular species, including the Huma Huma Trigger (R. aculeatus) and the Rectangular Triggerfish (R. rectangulus). While fish of this genus are without a doubt some of the most easily kept and sociable of all trigger species, they are also very slow growers - annoyingly slow if truth be known. If you want a nice adult show specimen, you have a true exercise in patience ahead of you unless you purchase an individual that’s already in the 7 or 8” range. For this reason, a young specimen, say in the 2” range can be purchased and comfortably housed alone in a 40-gallon tank for at least 12 to 18 months before larger quarters are needed. Long term, 70 gallons will generally do since once they reach 5” or so, their growth slows down even more. The above can also be applied to the Undulatus Trigger (Balistapus undulates). The primary difference here is that an Undulatus MUST be kept alone, for they are without a doubt the most aggressive aquarium species available, either freshwater or marine!
A few commonly seen species get quite large, and grow at a much faster rate than our beloved Rhinecanthus species. Among these are the Niger Trigger (Odonus niger), the Queen Trigger (Balistes vetula), the Clown Trigger (Balistoides conspicillim) and the Blue Line Trigger (Psuedobalistes fuscus) All four are relatively fast growers and require very large tanks as adults. We’re talking 500 gallons plus for the Queen, and at least a 200-gallon tank for the remaining 3 species. Of the four, only O.niger generally makes a good tank mate over the long term when kept with other fish, while the enormous size and aggression displayed by the Queen Triggers makes long term cohabitation with other fish all but impossible. The Clown Trigger and Blue Line fall while quite aggressive, are still a bit more social that the Queen, and if acquired small can live quite comfortably in a 55 or 70 gallon tank for some time before a larger tank becomes necessary, and they will even coexist with other species for a time if enough space is provided. This almost always changes at some point though, so be warned! The Queen grows much too quickly to consider anything but a very large tank from the get go Having said all this, a tank of at least 70 to 80 gallons will provide sufficient space on a long term basis for the vast majority of Triggers that you’re likely to encounter at your local fish store if kept alone. Even with the more sociable species, you will be very limited as far as suitable companions unless even more space is afforded.
Selection :
As mentioned above, Triggerfish are highly resilient animals, and for the most part they ship well and feed from the time they are collected to the time they make it into your home aquarium. Unlike members of some other genera, adult Triggerfish generally ship well and thrive in captivity, as to quite young specimens above the 1.25” mark. However in this hobby, as with all things, nothing is all the time, and Triggers can and do become sick deteriorate if not cared for properly after collection. When looking for a suitable animal, make sure that it’s robust, with no concave or sunken regions on its flanks. One of the most common problems is emaciation due to lack of proper nourishment, and a fish that’s not of proper weight should be avoided. The prospective keeper should also watch for cloudy areas or spots on the eyes, fins and body, as well as poor color. Very small specimens can sometimes be difficult, and some species are more prone to problems here than others. One the worst in this regard is the Clown Trigger, and very small specimens under an inch in length often last only a matter of weeks in captivity. Still, bear in mind that the Trigger should be the smallest fish in the tank (for those species where cohabitation is a reasonable option) and specimens in the 1.5”range and larger usually make an excellent choice. Of course, the Trigger must be of sufficient size to prevent it from being consumed by larger piscivores that might already be present in the system.
Introduction :
As mentioned above, certain species of Triggerfish are more appropriate than others for long-term cohabitation with other fish species. Some are just too large and/or aggressive to expect them to live successfully a community setting for more than a short time. While these species can certainly be kept with other species when small, attempting to keep them in a community setting once they begin to put on some size usually ends in tears – these are very powerful, and potentially very destructive fish. The advice given here is meant to provide the keeper with a long term husbandry solution.
Fortunately there are species that usually do quite well when mixed with other tough marine species in large quarters. Among the most commonly seen species that fit this description are those of the Rhinecanthus genus, which includes R. aculeatus, R. assasi and R. rectangulus. More than one Triggerfish from this genus can even be kept in the same tank, but they should be introduced at the same time to avoid serious territorial aggression. Also, despite it being a larger species, Odonus niger does quite well in a mixed species setting provided the tank is large enough to accommodate it’s considerable adult size, in the 20” range. Unlike some species, this one willgrow to full adult size in reasonable time if cared for properly.
The Halfmoom and Bursa Triggers, (Sufflamen chrysopterus), and (Sufflamen Bursa) respectively can also be kept in a community setting, as can the Pinktail Triggerfish, (Melichthys vidua), the Bluechin Triggerfish, (Xanthichthys auromarginatus), the Crosshatch Triggerfish, (Xanthichthys mento), and the Sargassum Triggerfish, (Xanthichthys ringens). The latter 4 species, as well as Odonus niger have the distinction of being generally safe in reef settings, with the caveat that small shrimp should be added before the Triggerfish, and the Triggers themselves should generally be added last, and be the smallest fish in the tank. In fact, in all cases your Trigger should be the last and smallest fish added to the community. The reason for this is that even relatively peaceable species like the Huma Huma, are only peaceable in relative terms! They are still somewhat aggressive fish, and can do a fair amount of damage in an altercation. For this reason they generally should not only be added last, but also be the smallest fish in the tank. This mitigates the damage that these fish are capable of, and allows the Trigger to become conditioned to the presence of his/her tank mates. Simply following these two rules generally assures that the Trigger does not establish itself as the dominant fish in the community, and allows the other inhabitants to adapt to the presence of the Triggerfish. For their part, Triggers are not generally susceptible to stress from larger, bullying tank mates, and they are quite well armored against anything short of a depth charge attack!
Ok then, what the heck can I keep with it?
Fortunately you have many choices in this department, and if we’re talking about O. niger, M vidua, or one of theXanthichthys species, your choices are almost unlimited. These species can be kept in reef setups, and often to even bother small shrimp if the shrimp are introduced before the Trigger. For the purposes of this section though we’ll assume that we’re talking about a Rhenicanthus species, a Sufflamen species or ‘gulp’ a young Clown or maybe a Blueline Trigger. Remember, you can keep them in a community for a while, and the fact that many people do is the reason why I mention them here. Unfortunately, this practice is normally the result of ignorance rather than the knowledge that sooner or later other living arrangements will have to be made. I include them here because I know that no matter what I say here, people will do it. Just remember, soon or later something will have to give! I can’t in good conscious include the Undulates even with a disclaimer. This author witnessed a 2”Undulatus attack a 15” Queensland grouper seconds after being introduced into a 200 gallon aquarium.(We won’t get into how appropriate it was to be keeping a grouper that attains a length of ‘cough’over 8’) The Trigger barely had time to take a breath before it was biting the much larger fish…relentlessly I might add. Total elapsed time for the “maybe I’ll get lucky and it will work for me Undulatus cohabitation experiment” – 90 seconds. This small chunk of empirical data, coupled with testimonials from numerous other aquarists leaves me no qualms about stating that this fish should not be kept together with other non-food item fish…ever. A few anomalous occasions where people can get away with it for a short time (it’s happened) shouldn’t persuade you to try it – be warned!
Having said all of this, as long as the aquarist follows a few rules and employs some common sense, tank mates are not hard to come by – there are actually plenty of choices.
These fish are beautiful, hardy and intelligent, and contrary to common perception, not generally aggressive toward members of other families. They are however more than assertive and robust enough to hold their own in the presence of most Balistoids. True groupers of the genus Epinephelus make great tank mates as well, as long as you obtain one the few species that remain small enough to be kept in a large home aquarium Within this genus, a few of the better choices are E. ongus, E. hexagonatus, E.merra. One simply needs to make sure that the sizes and growth rates of the fish are taken into account so that the Trigger does end up being a late night snack for the Grouper or Hind in question.
The larger, hardier angel species do well with Triggerfish, as do many wrasse, surgeonfish, and damselfish species, as well as various moray eel species.
Lionfish are often falsely lumped into the “aggressive fish” category like the Hinds, yet unlike the Hinds I cannot recommend them as tank mates for most Triggerfish species Some of the more rambunctious Triggers may harass the Lionfish and even nip spines off. In fact, various degrees of physical trauma is a danger with any slow moving or relatively sedentary fish species kept with certain Triggers. Back when I was younger and working at a local fish store, I witnessed an adult Clown Trigger remove the eyes from a 2’ Cat Shark soon after being introduced into a 400-gallon aquarium. An unfortunate incident, and a reminder that the destructive potential of these fish should not be underestimated, and tank mates need to be chosen wisely.
Remember, careful tank mate selection which takes into account size, including initial relative size and growth rate, and stocking order are 3 things to that must be strongly considered when stocking your mixed species tank. Triggers almost without exception should be the final fish added.
What if I want to keep him alone?
Then you’re in for an extremely rewarding and entertaining experience, and only the size tank you can invest in limits your choice of Triggerfish. Keeping a single fish alone in a species tank is the only viable option for certain species, including B.undulatus, and V. vetula – the Undulated and Queen Triggers respectively. In fact, of the dream tanks that this author aspires to keep on day is a 120 gallon tank with a single, adult Undulates Trigger. For the B. Vetula, the 2’ Queen Triggerfish, it will have to be a tank in the 500 gallon range. Now the aquarist is only faced with the challenge of dealing with the highly destructive capabilities of these fishes, and nothing is safe! This means filters, powerheads, power cords and heaters! For this reason, these items are best kept in a sump, and out of the main tank. They are also adept, (and seemingly quite fond of), overturning and moving rocks and other pieces of décor. This tendency should be taken into account when aquascaping a tank that will eventually house and adult Triggerfish.
Speaking of things that should be kept out of the main tank, add your hands and arms to the list! As much as possible anyway, you should avoid inserting your hands into a tank containing a large Triggerfish – they can draw blood, and larger specimens (though unlikely to be found in your home tank) can remove fingers. The jaws of these fish are highly effective at what they are designed for, which is dismantling all manner of hardened items found in their environment. Always be aware of where your Triggerfish is when doing maintenance of your tank, even smaller specimens can deliver a painful and shocking bite.
Feeding :
The news couldn’t be better in this department – feeding a Triggerfish is the easiest thing you can imagine. Most species feed on hard shelled invertebrates in the wild, so they spend their day browsing the reef for crabs, shrimp, snails, etc. In captivity, they will accept a wide range of fresh and prepared fish foods, only leaving the aquarist the task of making sure that a variety of food items are offered, and that vitamin supplements are administered now and then to insure proper nutrition. Aside from a variety of appropriate foods that can be purchased in frozen form at most better fish stores, the aquarist can brows the seafood counter at his or her local grocer, and find many things that will have a Triggerfish eating out of the keepers hands in no time flat. A few of these items are fresh squid, octopus, scallops, fish, shrimp and crab. These foods can be cut into bite sized morsels and offered to the Trigger 2 or 3 times a day. Whole crayfish can even be offered, shell and all, and this will allow you to witness the business end of a Triggerfish doing what it was meant to do…demolish and consume! Even the few available species that are planktivores in the wild readily accept and thrive on all the options mentioned above with the exception of large, whole invertebrates.
Too big for all but the largest of aquariums, this Titan Triggerfish, (Balistoides viridescens), grazes in the company of several Undulated Triggerfish (Balistapus undulatus)
One thing bears repeating here, and that is the importance of vitamin supplements. The primary reason for this is that feeding a predatory animal of any kind (be it bird, reptile, or fish) meat only does NOT replicate it’s natural diet in full. The predator in question is a consumer of whole animal items. When a Trigger consumes a crab in the wild, it not only ingests the meat, but all the blood, organs and other matter other that makes up the animal - not simply meat. Feeding a combination of whole food items and vitamin supplements mitigates any problems that my rear their head down the road due to improper nutrition, including but not limited to, poor color.