Blue Tang – 5 Interesting Facts And Information To Know

Blue Tang

Last updated on August 19th, 2022 at 11:42 pm

The blue tang is a surgeonfish, a group of fishes called for the scalpel-like spinal column on the side of the body, simply ahead of the tail. The fish, like all surgeonfishes, use these spinal columns to resist predators. They erect the sharp spinal columns in an effort to make themselves more difficult to swallow or to cause injury to their predators.

They can be discovered in the clear waters of coral reefs. Professionals think that as numerous as a quarter-million of them are taken from the wild each year for the aquarium trade.

COMMON NAME: Blue tangs
TAXONOMIC NAME: Paracanthurus hepatus
TYPE: Fish
DIET PLAN: Herbivore
SIZE: 10 to 12 inches
WEIGHT: One pound

Fast Truths About This Fish Type


Blue Tang

Blue to deep purple, ovoid body with white or yellow spine along caudal peduncle. The intermediate kind has a blue body and yellow caudal fin. The juvenile type has a yellow body with a light blue edging along with the dorsal and anal fins. The dorsal fin is continuous from the gill plate to the caudal peduncle. Somewhat centrally cleft (emarginate) caudal fin.

Size: 12 to 25 cm (5 to 10 in.) avg; 38 cm (15 in.) max

Weight: 600.0 g (1.6 lbs.) avg

Diet: Marine plants and sediment


When reproducing, they will gather – forming spawning aggregations. Within these aggregations, they release gametes into the water column – presenting pelagic eggs. These eggs then incubate over the next number of weeks to months following their release.

Sexual Maturity
Male: 11 cm (4.3 in.).
Female: 13 cm (5.1 in.).

Range: Western Atlantic: New York (seasonal) and Bermuda to Gulf of Mexico and Brazil.

Eastern Atlantic: Ascension Island.
Habitat: 2 to 40 meters (7 to 130 feet) in tropical & subtropical marine coastal waters.


Worldwide: International population data are not presently available; however these fish types in not consider threatened or endangered.

Blue Hippo Tang Fish "Paracanthurus Hepatus"

Regional: In a ten-year research study carried out in the waters adjacent to the Virgin Islands, blue tangs were found to be more plentiful than any other fish types, representing an observed 15.4% of the region’s total fish population.

What is a blue tang?

Paracanthurus Hepatus

Blue tangs are little fish belonging to reefs in the Indo-Pacific. The animals are simple to identify, thanks to their characteristically lively colorations of royal blue and canary yellow.

The blue tang’s well-known color patterns are not as reliable as you may believe. Juvenile blue tangs are intense yellow. And as adults, the fish will flush deeper blues and violets as an indication of tension.

Blue tangs might look reasonably safe, but when in risk they can raise a set of razor-sharp, venomous spines on either side of their tails. The fish then whip their bodies from side to side, threatening to stab predators with their toxin-tipped stingers.

Additionally, people who eat blue tangs have actually been understood to establish a major foodborne health problem called ciguatera poisoning. Signs include lightheadedness, throwing up, and diarrhea. Ciguatera poisoning happens since tangs often eat big amounts of animals called dinoflagellates, which create several kinds of toxins that build up in the tang’s body.

Mistaken identities

The blue tangs go by many typical names, including scheme surgeonfish, regal blue tang, hippo tang, flagtail surgeonfish, royal tang, Pacific regal tang, and blue surgeonfish.

There are also a number of other fish types that are sometimes referred to as blue tangs, including Acanthurus leucosternon, which can be distinguished by its black face, and Acanthurus coeruleus, which resides on the opposite of the world in the Atlantic Ocean.

This is why professionals assign animals taxonomic names in Latin. While there are many blue tangs, there is only one Paracanthurus hepatus.

Habitat and diet

Blue tangs can be discovered in the clear waters on and surrounding reef. They populate a large range across the Pacific and Indian Oceans that stretches from American Samoa to the eastern coast of Africa.

While blue tangs are omnivores and have actually been known to consume small marine animals referred to as plankton, the bulk of their diet plan comes from algae. The fish use small, sharp teeth to nip and scrape algae off the coral reef.

Amazing Blue Clownfish "Tap Tap Fish"

This makes the fish essential cogs within the bigger community. Without blue tangs and other fish that perform this algae-cleaning service, the plants would suffocate and eliminate coral, sending out the entire food cycle into disarray.

Threats to survival

While the fish is noted as a type of least issue by the International Union for Conservation of Nature (IUCN), there is some fret about the method the fish is targeted by the fish tank trade. Till 2016, no one understood how to reproduce blue tangs in captivity, which indicates that all of the fish being offered into the market were sourced from the wild.

Professionals say this might mean as many as a quarter-million blue tangs have been removed from their houses on reefs each year.

Worse still, blue tangs and other wild reef fish are frequently captured with squirt bottles complete of cyanide, which stun the fish long enough for people to catch them. Since they flock to stony corals where they can be captured en masse, juveniles are generally targeted. That technique can likewise kill the fish on contact, as well as injure or eliminate other animals nearby.

The reef that the blue tangs call home is also at risk from things like ocean acidification and coral lightening or bleaching. This indicates environmental loss might likewise be a risk to the fish.

Ecology and Conservation

Blue tangs mainly count on marine algal species for nourishment. Algal resources readily available within the tang’s environment are frequently things of high competition. Perhaps most significantly, private and/or paired damselfish prove to be incredibly effective in their defense of an algal grazing territory.

Blue tangs, however, are typically finding success in overwhelming these strongly protected areas through the formation of large grazing aggregations. Current modifications in algal neighborhoods throughout the Caribbean have had considerable influence on the populations of blue tangs.

Motions of blue tangs are mainly limited to single reef environments, though they are comprehensive over said reef. Appropriately, a particular environmental effect over a specific reef site might exert extreme pressures over a local blue tang population.

Abudefduf Sexfasciatus (Scissortail Sergeant)

Blue tangs are a popular saltwater fish tank specimen. They are typically gathered from the Caribbean basin for introduction into the commercial aquarium trade.

Fun Facts 

  1. The blue tang’s scientific order, Perciformes, is the largest vertebrate order with 148 families including roughly 9,300 species.
  2. Blue tangs are capable of changing the intensity of their color from light blue to deep purple.
  3. Blue tangs are frequently found swimming in large schools traveling over the reef top, grazing on algae. These collections are frequently made up of several types within the Acanthuridae (surgeonfish and tangs) family.
  4. The blue tang has a sharp spine, or customized scale, located along either lateral edge of the caudal peduncle. These spines may be made to stand put up, giving the tang effective methods of self-defense.
  5. The flesh of the blue tang is harmful.

The Issue With Wild-Caught Blue Tang

Paracanthurus Hepatus

Barden leans over a 700-gallon (2,650-liter) fiberglass tank in a humid greenhouse at the Tropical Aquaculture Lab in Ruskin, Florida. It’s April 2016, and Barden, who focuses on the aquaculture of marine species, speaks passionately about the tank’s occupants.

His eyes follow the deep blue flashes and streamlined glides of two adult Pacific blue tangs – the types that has actually occupied much of his expert life since 2012.

The fish is a popular, high-value fish tank species. Trade data reveal that out of almost 2,300 saltwater aquarium fish types imported to the U.S., blue tangs have actually been ranked as high as the 10th most imported fish, thanks in part to their appealing colors and relative price.

According to the Marine Aquarium Biodiversity and Trade Flow database, more than 130,000 blue tangs reached U.S. markets in 2009, and due to the fact that the U.S. is usually assumed to represent around half of the global trade in tropical fish, the total number of blue tangs reaching international markets likely goes beyond a quarter of a million per year.

This figure doesn’t consist of fish that pass away early in the supply chain and for that reason aren’t counted in the best readily available trade data.

Gray Angelfish - Pomacanthus Arcuatus


True blue tangs are restricted to reef in the Caribbean Sea and surrounding waters and are frequently confused with two other surgeonfishes that populate the same waters, the doctorfish and ocean surgeonfish, and all the three species look similar.

In addition, another surgeonfish that resides in the tropical Pacific Ocean (and was made well-known as Dory in the Finding Nemo motion pictures) is sometimes incorrectly called a blue tang. That types (Paracanthurus hepatus) is more effectively referred to as the regal tang or powder blue tang, and it does not closely resemble the blue tang, visually.

They are herbivores, and they actively search the surface of coral reefs, looking for their favorite algae. Bigger individuals often search by themselves or in sets or threesomes, little to medium grownups often form big groups and swim long distances, searching along the reef surface throughout the day.

With overfishing of their main predators (e.g., large groupers and snappers) and a decrease of a few of their primary competitors for algae (e.g., the Longspine Urchin), numbers of the adult can be quite high up on lots of reefs.

Juveniles live amongst dead coral debris or in mangrove forests in more safeguarded waters and move to the open reef surface area as they mature. Adult blue tangs are strong blue (or almost dark purple), while juveniles are solid yellow.

They replicate through a habit called broadcast spawning, where a number of females release eggs and numerous males release sperm into the water column above the reef, all at the exact same time. This technique increases the likelihood that eggs will end up being effectively fertilized and that fertilized eggs will not be eaten by egg predators on the reef surface.

They are eaten by humans only rarely when caught in artisanal fish traps, but brilliant yellow juveniles are targeted rather significantly in some areas for the private aquarium trade.

Nevertheless, researchers have actually examined the blue tang’s population status and have actually discovered it to be a species of least concern (i.e., its numbers are presently fine).