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Boxfish :

  • Group: Saltwater

  • Size: Medium/Large

  • Temperament: Community Aggressive

  • Aquarium size: Large (55 gal+)

  • Swimming Region(s):Middle

  • Water Conditions:Specific Gravity – 1.02 – 1.025 – Temperature -22°-26° Celsius

  • Suitable Tank Mates:Butterflies, Clownfish, Gobies, Damsels, Hogfish, Parrotfish and Tangs

  • Difficulty Of Care:Weekly care

General description : 

 

Also known as trunkfish, cowfish and cofferfish; boxfish are a family of bony marine fish. They are characterized by their square shaped body and heavy armored scales. Due to their odd shape and heavy scales, they are extremely slow swimmers. Juveniles are more rounded in shape and exhibit brighter colorations than their adult counterparts. Various species grow to different sizes ranging from 3 to 18 inches.

Also known as trunkfish, cowfish and cofferfish; boxfish are a family of bony marine fish.

Origins:

Boxfish originate primarily in the Pacific Ocean.

Color:

Boxfish come in a variety of colorations ranging from yellow, blue, brown and black.

Maintenance and care:

 

One of the most important things to remember when choosing tank mates for boxfish is that they should not be kept with aggressive or predatory fish. When feeling threatened or stressed, they are known to emit a toxin through their skin which can harm and even kill other species of fish. For this reason it is best to keep boxfish with more peaceful tank mates. These fish are generally peaceful towards other species of fish but can turn aggressive towards members of their own species. If keeping more than one boxfish in an aquarium it is advisable to only attempt to keep two or more females together.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Another important consideration when choosing boxfish is their potential size. The different species of boxfish have varying sizes and it is important to research their growth potential before deciding to purchase them. They also thrive in aquariums with plenty of hiding places and open swimming areas. They also prey on invertebrates and will attempt to eat any coral in an aquarium, making them unsuitable for reef aquariums. Boxfish are hearty eaters produce a significant amount of waste making an adequate filtration system a prime concern for the aquarium.

Feeding : 

 

It is important to feed boxfish on a varied diet of both meaty and vegetarian foods. They will readily accept meaty foods such as shrimp, crab meat and mussels and green foods such as frozen peas, boiled lettuce and dried seaweed.

 

Breeding :

 

Breeding boxfish is not a task that has been achieved with any regularity in the aquarium.

 

Aquarium varieties  : 

 

Yellow Boxfish, Bluespotted Boxfish, Longhorned Boxfish, Buffalo Boxfish, etc.

 

Boxfish Tankmates :

 

courtesy to : www.fishchannel.com 

 

Q. I have freshwater and saltwater tanks, and believe your coverage of both is very balanced. I am interested in keeping a yellow boxfish (Ostracion cubicus) in my reef tank. I have heard several different opinions on whether this is possible or not. One shop owner even told me that you couldn't keep boxfish in a tank with other fish because they release a toxin that will kill everything in the tank. Is this true?

 

I have many soft corals in my tank, with a couple of open brain corals and an elegance coral. Any information you can give me on how to keep this fish would be much appreciated! Keep up the good work AFI!

 

A. The box, or trunkfishes, belong to the family Ostraciidae and are some of the most comical looking fish on the reef. They are encased in a bony carapace that has holes where the eyes, mouth, gills, anus, fins and tail fin base are. They are slow swimmers that move primarily by sculling with their dorsal and anal fins. They use their tail fin for sudden bursts of speed.

 

Not only do these fish rely on armor plating to deter would-be predators, they also have a chemical defense. This consists of a potent toxin, known as ostracitoxin, which they exude in their slime when they are stressed. When secreted into the aquarium water, this toxin can kill other reef fishes at concentrations as low as 10 parts per million, and the secretions of a single adult boxfish can contain as much as 50 to 100 milligrams of crude toxin (Thomson 1964)! Although they are less susceptible to ostracitoxin, boxfishes are often killed by their own secretions in a closed system. A boxfish could kill every fish in a medium-size aquarium within 10 minutes.

 

However, even though a boxfish can be lethal to its tankmates, these types of episodes are very rare if precautions are taken. I have kept numerous boxfishes, and have also sold many specimens, and only know of two occasions where individuals "nuked" a tank.

 

The most important thing you can do to reduce the likelihood of this happening is to keep your boxfish with passive tankmates. If other fishes are harassing a boxfish, it is more likely to exude ostracitoxin. Some obvious species you will want to exclude include morays, larger dottybacks, snappers, aggressive angelfishes, larger damselfishes, surgeonfishes, triggerfishes and puffers. A less obvious group of fishes that should be avoided that are known to pester boxfishes is the cleaner wrasses (Labroides). These wrasses often chase and pick at the less maneuverable boxfish when the boxfish doesn't want to be cleaned.

 

Boxfishes are rarely aggressive toward non-related species, so they can be kept with species with similar dispositions, like anthias, grammas, chromis, flasher wrasses, gobies and fire fishes. Very large boxfishes have been reported to eat smaller fishes, but these incidents are rare.

 

If you want to house more than one boxfish in the same tank, keep a male and a female. It's also possible to house two females together in a larger aquarium, but never keep two males in the same tank. Fortunately, most of the Indo-Pacific members of the genus Ostracion are easily distinguished, with males attaining a larger size and usually displaying dramatically different color patterns. In the case of the yellow boxfish, females are yellow with black-bordered white spots, while males are larger and are purplish brown with faint spots (males are rarely seen in the aquarium trade). Both male and female juveniles are yellow with black spots. There is still debate as to whether boxfishes do or do not change sex from female to male.

 

When working in the aquarium (arranging decor or cleaning the tank), move your hands very slowly and never corner the boxfish. If you have to catch a boxfish, use a specimen container and place it against the front glass of the tank. Then slowly herd the boxfish into the container. Never chase the boxfish around the tank with a net. Maintaining good water quality in the aquarium also reduces boxfish stress.

 

One of the most dangerous times for the boxfish keeper is when the fish is transported from the dealer's tank to the home aquarium. During this process it is likely to become highly excited and distressed. This is when they are most likely to exude the toxic secretions. To reduce stress during transport place the boxfish in a cooler and keep it in the dark until you get it home. When you move the boxfish from the bag to the aquarium, pour off as much of the water in the bag as possible and then pour the remaining water and boxfish into the tank.

 

The most obvious indicator of boxfish poisoning is the behavior of the other fish in the aquarium. Symptoms include nervousness and gasping, followed by inactivity and a decrease in respiration. Finally, the fish will begin moving sporadically, convulse and die. Once the initial symptoms are exhibited it is usually too late to revive the suffering fish, even if you quickly move them to another tank (although it never hurts to try and save them). Another sign of poisoning is the presence of foam on the water surface.

 

If you really want a boxfish, but are worried that it may kill your other fish, you can always keep it by itself in a specimen tank. The yellow boxfish will need a tank of at least 75 gallons because it can attain a length of about 18 inches, but other species can be kept in tanks as small as 30 gallons. As indicated above, these fish rarely poison their tankmates, but I would not place a boxfish in a tank with extremely valuable fish.

 

Certain boxfish can present feeding problems. Some individuals will ingest food as it sinks when they are initially introduced to the tank, but most prefer to feed off the substrate. If there are aggressive feeders in the tank with a boxfish, it may never get enough to eat.

 

The best way to entice a finicky boxfish is to add a piece of live rock that is encrusted with invertebrates and algae. If you don't have access to live rock, you can press frozen prepared food or fresh seafoods, like shrimp, into the small openings on a dead stony coral where the polyps were, and add this to the tank. Make sure you remove any uneaten food after a few hours have passed. Once it begins feeding in captivity you can usually switch a boxfish over to normal aquarium fare, including finely chopped fresh seafoods, krill, brine shrimp, mysid shrimp, live black worms and even flake food. When they fully acclimate they will even take food from your fingers. A tank with a healthy algae crop can help meet a boxfish's nutritional needs as well.

 

If you feed flake food or any other food that floats, make sure you saturate it with water before adding it to the tank so it sinks immediately. It is possible that a boxfish will ingest air when feeding at the surface and may have difficulty expelling it. This can cause buoyancy problems, with the boxfish having difficulty maintaining its position in the water column. Often it will swim with its tail well above its head, and may end up wedging itself between rocks or under a piece of coral. If this occurs you can only hope that the fish expels the air through its mouth or anus.

 

I have also seen these fish unintentionally get stuck between aquarium decor and the aquarium glass, between the glass and the uplift tube of the undergravel filter, or between rocks. I have even seen them get stuck on top of an undergravel uplift tube that was just submerged under the water's surface! Take these things into consideration when aquascaping the boxfish aquarium. Boxfishes often contract ich (Cryptocaryon irritans), but can be treated with the common antiparasitics (copper-based medications).

 

The boxfishes feed mainly on sessile invertebrates like tunicates and sponges. However, the yellow boxfish also is reported to ingest ploychaete worms, algae, small bivalves, gastropods and even small fish. Although most boxfishes don't typically eat corals in the wild, they may nip at, and even eat them, in the confines of an aquarium. They are more likely to ignore larger soft corals, like Cladiella, Sinularia and Sarcophyton, but may pick at small-polyped (e.g., Anthelia, Xenia) and large-polyped stony corals (like your open brain and elegance corals). Boxfishes will also nip at small-polyped stony corals, fan worms, tridacnid clams and echinoderm tube feet, and eat sponges and tunicates. I have never had a boxfish "nuke" a reef tank, but the toxin is known to kill some invertebrates.

 

A final note: Boxfishes apparently vary in the potency of their toxin and their propensity to exude it. The members of the genus Ostracion are the most dangerous species to keep with other fish, while the cowfishes of the genusAcanthostracion and Lactoria and the Atlantic trunkfishes of the genus Lactophrys rarely, if ever, cause problems.

 

 

References

Thomson, D. A. 1964. Ostracitoxin: An ichthyotoxic stress secretion of the boxfish, Ostracion lentiginosus.Science

 

1 - Longhorn Cowfish (Lactoria cornuta) :

 

Minimum Tank Size: 250 gallons

Care Level: Difficult

Temperament: Peaceful

Reef Compatible: With Caution

Water Conditions: 72-78° F, dKH 8-12, pH 8.1-8.4, sg 1.020-1.025

Max. Size: 1' 8"

Color Form: White, Yellow

Venomous: Poisonous When Stressed or Dies

Diet: Omnivore

Compatibility: View Chart

Origin: Indo-Pacific

Family: Ostraciidae

The Longhorn Cowfish inhabit the reefs of the Indo-Pacific, usually in the less turbid waters. The body is tan to yellow and covered with white and blue dots, and is occasionally referred to as the Yellow Boxfish; however, the Longhorn is not to be confused with Ostracion cubicus, commonly called the Yellow or Polka Dot Boxfish. In the wild, it is not uncommon to see a 20" specimen, while in the aquarium the Longhorn Cowfish tends to be dramatically smaller - 16" or less.

 

When possible, the Longhorn Cowfish should be the first fish introduced in the tank. It is intolerant of other Longhorns, so keep it in a large tank, with some live rock for algae scraping. Use caution if placing the Cowfish Longhorn in a reef tank as it may nibble on tubeworms. When housed correctly, the Cowfish Longhorn is long-lived.

 

Similar to other boxfish, the Cowfish Longhorn's skin is poisonous and, when threatened, it will release a toxin lethal to other tank members, including other Longhorns.

 

Since they are omnivores, the Longhorn Cowfish should be offered a variety of meaty and vegetable foods. They are slow eaters, and should not be housed with aggressive eaters.

 

Approximate Purchase Size: Small: 1" to 2-1/4"; Medium: 2-1/4" to 3; Large: 3" to 4-3/4"

 

Caution: This species secretes or releases toxins when stressed or injured that may kill fish in the aquarium. LiveAquaria.com cannot accept responsibility for any loss that may occur should this animal poison the aquarium.

2-Cubicus Boxfish

Ostracion cubicus 

 

Minimum Tank Size: 125 gallons

Care Level: Expert Only

Temperament: Semi-aggressive

Reef Compatible: With Caution

Water Conditions: 72-78° F, dKH 8-12, pH 8.1-8.4, sg 1.020-1.025

Max. Size: 1' 6"

Color Form: Blue, Green, Tan, Yellow

Venomous: Poisonous When Stressed or Dies

Diet: Omnivore

Compatibility: View Chart

Origin: Indo-Pacific

Family: Ostraciidae

The Cubicus Boxfish is also referred to as the Yellow Boxfish, Polka Dot Boxfish, or Cube Boxfish. The juvenile form is easily identifiable as having a yellow box-shaped body with brown spots. As an adult, the yellow will fade and become brown. The Cubicus Boxfish is sometimes confused with the Longhorn Cowfish, Lactoria cornutawhich is occasionally also called the Yellow Boxfish.

 

This is a very difficult fish to keep in the aquarium setting by any other than the most experienced aquarist. It should have a minimum of a 125 gallon tank. Use caution if placing the Spotted Boxfish in a reef tank as they will often nibble at tubeworms. If stressed, the Cubicus Boxfish releases a poisonous substance, called ostracitoxin, from its mucous glands which will kill other fish in the tank very quickly.

 

Very little success has been achieved in breeding these fish in an aquarium.

 

When first introduced, the Cubicus Boxfish prefers a diet of live brine shrimp or bloodworms. Once acclimated, the diet should include chopped squid, clams, mussels, and herbivore preparations.

 

Approximate Purchase Size: Tiny: 1-1/2" to 2-1/4" Small: 2-1/4" to 3"; Medium: 3" to 4; Large: 4" to 5"

 

Caution: This species secretes or releases toxins when stressed or injured that may kill fish in the aquarium. LiveAquaria.com cannot accept responsibility for any loss that may occur should this animal poison the aquarium.

Polka-dot Boxfish

Yellow Boxfish, Blue-spotted Boxfish

Family: Ostraciidae

 

courtesy to  www.animal-world.com 

 

Article by Elizabeth M. Lukan

Ostracion cubicus

 

The young Yellow Boxfish has an almost perfect box shaped body which becomes more elongated as it grows older.  It also changes from the yellow or cream color when young to different colors when older, mostly yellow-green.  The spots also change from dark-blue in the young fish to white with blue rings in the adult.  The body is enclosed in a bony structure covered with a thin layer of skin with fins sticking out and no spiny dorsal fin.

 

Scientific Name : Ostracion cubicus

 

Boxfishes belong to the Tetraodontiformes order which also includes puffers, porcupinefish, and triggers.  Boxfishes belong to the Ostraciidae family.  Boxfishes are also commonly called cowfishes and trunkfishes (for example, the popular, Long Horned Cowfish - Lactoria cornutus).

 

Home Aquaria:

 

Although many of the offerings in the fish stores are tiny, some as small as a dime, these fish can grow to 15-18 inches, therefore a large aquarium is recommended - 100 gallons and up.  Boxfish like to hide, so hiding places should be offered and will provide a retreat from any perceived danger.  The Yellow Boxfish requires no special lighting or temperature, very good tank conditions and water parameters are needed.  Strong water movements cannot be handled by the young boxfish as they are slow swimmers.  Make sure they can't get sucked into any powerheads or filters you may have.  They should be kept in Fish Only tanks as they will pick on (eat) soft corals, tube worms, etc. in reef tanks.  The Yellow Boxfish should never share an overcrowded tank or have aggressive or fast moving tankmates.  The Yellow Boxfish will swim all levels of the tank (top, middle, bottom).

 

According to Mark Taber's Survey On Fishkeeping (from Albert Thiel's website (http://www.athiel.com) and posts to rec.aquaria.marine.misc and rec.aquaria.marine.reefs newsgroups) which quoted Frank M. Greco's list of fish unsuitable for captivity, the Yellow Boxfish should not be kept in the home aquaria.  The fact that boxfish are so prone to ich was the reason for their being added to the list.  Per Mr. Greco, "...a survey I did of local area wholesalers found that a minimum of 30% and a maximum of 100% of these fishes died.  Necropsy found that most, if not all, of these animals were infested with Amyloodinium and Cryptocaryon.  The degree of survival past the wholesaler/shopowner portion was small as well, if memory serves.  And, these fishes tend to be copper sensitive to boot, IME (in my experience) with them.  So utilizing copper on these fishes during quarantine seems to cause more problems than it's worth.  Many die from it and those that do not are never quite right afterwards.  Malachite green is a good substitute, but it's just not as effective as copper."

 

While conversing with Mark and Frank to obtain their okays to quote, Frank requested that I also add the following to the article.  "...you should also note that my designation of this fish as difficult is, at best, a subjective one.  My reasonings behind listing this fish thusly are, IMO (in my opinion), sound ones.  But, as in almost all cases, my experiences may not be the same as those of others.  It is important that this be made known.  My listings are not absolute, nor should they be taken that way."

Foods & Feeding:

 

Before bringing your boxfish home, make sure it is eating at the store.  You must be 100% sure your fish is eating.  A  boxfish that isn't eating may already be stressed and any stressed fish won't survive long, especially a boxfish with their ability to release toxins and susceptability to Cryptocaryon, etc.  Larger and older fishes are harder to start feeding than younger ones.

 

Because they are naturally slow moving, shy, and rather clumsy, the Yellow Boxfish may very easily be outcompeted for food by tankmates, especially if the tankmates are aggressive fish.  It is vital that you make sure your boxfish is eating regularly.  If you keep your boxfish with more aggressive fish, it is best to feed them first, then concentrate on feeding your boxfish.  That way, competition for food will be less.

 

The Yellow Boxfish is an omnivore and will eat all kinds of live, frozen, flake, and veggie foods.

 

Small fish (dime size) can be offered live and frozen brine shrimp as well as cubed frozen food like Ocean Nutrition's Formula I and II (thawed or not, depending on how well it is taken).  If they refuse the Formula I or II, you may try adding it at the same time as the brine shrimp and they may try it and you can slowly decrease the brine shrimp offered until they have switched.  As they grow, they will develop a huge appetite and will even "beg" for food (swimming to you whenever you near the tank).  Overall, a variety of foods is best, including seaweed (Ocean Nutrition's Seaweed Selects or nori (dried seaweed used to wrap sushi - unseasoned).  As in last month's Kole Tang article, the seaweed can be offered in a suction cup clip or rubberbanded to a piece of rock or tank ornament.

 

Behavior: 

 

They are such slow movers that they are easily caught by hand.  They move awkwardly using their side fins and the tail fin only in case of emergency or to get food.  It is common for them to "sit" still in one spot for very long periods of time.

 

This fish can be extremely dangerous to other tankmates and itself.  If threatened or stressed, they can release a toxin into the water which will kill everything in the tank, including themselves.  Invertebrates are not safe from this toxin either.  They may also release this toxin on death.  If your boxfish looks diseased, stressed, or on the brink of death, it is vital that you remove it to a quarantine tank.  A boxfish close to death will be lethargic and will experience rapid color fading in the minutes or hours before death.  If one dies in the aquarium, remove it immediately, every second counts for the life of whatever else is in the tank.  Hobbyists report all livestock in a 65 gallon tank dead in an hour and animals dying within seconds of a boxfish death.

 

Because of this ability to release a toxin, the yellow boxfish, and boxfish in general, are usually considered to be for the more experienced hobbyists as they are better suited in maintaining a stable environment, etc.  Although it has been reported that they will rarely release this toxin, it is still a possibilty, and one best kept in mind when considering purchasing this fish.

 

If the tank has been hit with the toxin, hobbyists suggest the following to help combat it's effects:  remove fish to quarantine tank, perform 100% water change, make sure protein skimmer is running at top efficiency, add activated carbon to filtering system, when adding fish back do not put the water they are in back into the tank, another water change after system stabilizes (a week or so).  Removal of the toxin from the tank is not entirely possible as it will settle into live rock, ornaments, bio bed, filters, etc.  Using this method may prevent the death of your biological filter as the toxin is reduced and further dilution is possible through the subsequent water change(s), protein skimming, and addition of carbon.

 

Some reports note that this fish may or may not be aggressive towards it's own kind, therefore, care should be taken when adding a new boxfish into a tank with an established boxfish.  I cannot say for certain if this is true or not, but it was found in some of my research.  Most hobbyists mention the Yellow Boxfish's gentle nature (even so far as taking food from the hobbyists hand and being petted), but I couldn't find anyone having kept more than one in a tank so I cannot say if this is true or not.

 

Disease Fighting: 

 

Boxfish develop skin diseases easily (Cryptocaryon, etc.) and are very difficult to treat.  They cannot be treated with copper, which causes some controversy among hobbyists with some reporting success treating with copper, others report death, I prefer to go against using copper as my research shows more against than for.  Why take the chance with an animals life?  Do not give your boxfish a freshwater bath as is sometimes recommended as a treatment, as a matter of fact, avoid removing your boxfish from the tank as it will just stress them and a stressed boxfish may release it's toxin.  I would only recommend removing a boxfish, as I noted above, when already stressed, diseased, or on the brink of death.

 

Although they will survive nicely in normal water parameters, it is important to keep those parameters under control.  No ammonia, nitrites, etc.  If you let these parameters slip, you are asking for an outbreak of disease.

 

Boxfish will not tolerate cleaner wrasses well, but hobbyists report them allowing themselves to be cleaned by shrimp.  They don't like being cleaned by wrasses because they don't have scales.  Scaleless fish can be injured by cleaner wrasses who will harrass them long after there is anything left to clean and since boxfish swim so slow they can't easily get away.

 

Cost:

 

Store:  From $15 to $40 with a 12 inch one going for $80.  Two stores were checked in Queens, New York for prices.

Online: From $10 (small) to $14 (large). Two online sites were checked to obtain these prices.

This fish is only occassionally available through local fish stores, but is usually more available via online services.

3-Boxfish

Ostracion meleagris 

 

Minimum Tank Size: 180 gallons

Care Level: Expert Only

Temperament: Peaceful

Reef Compatible: With Caution

Water Conditions: 72-78° F, dKH 8-12, pH 8.1-8.4, sg 1.020-1.025

Max. Size: 10"

Color Form: Black, Blue, Orange, White

Venomous: Poisonous When Stressed or Dies

Diet: Omnivore

Compatibility: View Chart

Origin: Hawaii, Maldives

Family: Ostraciidae

The Boxfish is also referred to as the Spotted Boxfish, Blue Boxfish, Black Boxfish, or Whitespotted Boxfish. The various names are due to the dimorphic appearance of the male and female. The male is the more colorful of the two, with a vibrant blue body and a wide black swath covering the top of the body like a cap. The entire body is speckled with dots, white on black and black on blue while a thin horizontal stripe of orange adorns the tail. The female is entirely black with white dots.

 

This is a very difficult fish to keep in the aquarium setting by any other than the most experienced aquarist. It should have a minimum of a 180 gallon tank. Use caution if placing the Boxfish in a reef tank as they will often nibble at tubeworms. When stressed, the Boxfish releases a poisonous substance, called ostracitoxin, from its mucous glands which will kill other fish in the tank very quickly.

 

Very little success has been achieved in breeding these fish in an aquarium. When first introduced, the Boxfish can be fed a diet of live brine shrimp or bloodworms. After acclimatization, chopped squid, clams, mussels, and herbivore preparations can be fed.

 

Approximate Purchase Size: Small Female: 1" to 2"; Medium Female: 2" to 3; Large Female: 3" to 5"; Male: 3" to 4"

 

Caution: This species secretes or releases toxins when stressed or injured that may kill fish in the aquarium. LiveAquaria.com cannot accept responsibility for any loss that may occur should this animal poison the aquarium.
 

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