The Whitecheek Tang is a voracious algae eater… quite beneficial to a productive reef with lots of algae growth!
The Gold-rimmed Tang Acanthurus nigricans is a handsome fish. It has a disk shaped body with a brownish to black color, though on occasion it will quickly become yellow on the back half. It has white horizontal patch just under the eye and a narrow white band nearly encircling its mouth. It is also touched with a few other colors, like fins trimmed in electric blue and few yellow lines, one across the tail fin, and two others running just under the dorsal fin and above the anal fin, broadening as they near the tail. The scalpel is also surrounded in yellow while the tail fin is white, shading into a pale blue.
The coloring of this tang has led to a number of descriptive names. Its species name, “nigricans,” comes from Latin for “blackish,” hence the common names Black Surgeonfish and Blackear Surgeonfish. It is also referred to as the Whiitecheek Surgeonfish, Whitecheek Tang, and Powder Grey Tang in the aquarium trade. Some of the other common names include Gold-rimmed Surgeonfish, Gold-rim Tang, Golden Rimmed Surgeonfish, Gold Edge Tang, Yellowrimmed Surgeonfish, Yellow-fin Tang, Gray Surgeonfish, and Velvet Tang.
The Gold-rimmed Tang is also one of the surgeonfish often referred to as a ‘Powder Brown Tang’, the other being its very similar looking relative, the White-faced SurgeonfishAcanthurus japonicus. These are two of four species belonging to the “Achilles complex” (named after the the Achilles TangAcanthurus achilles). The fourth species is the popular Powder Blue TangAcanthurus leucosternon. These tangs all have similarly placed markings and also have ranges that overlap in some areas in the wild, lending a propensity to hybridize with each other.
The Achilles and Powder Blue Tang are easily identified members of the Achilles complex, but not these two “look-alike” cousins. They are very similar to one another, but can be distinguished by slight differences in their facial markings. The Gold-rimmed Tang has a white facial patch only under the eye while the White-faced Surgeonfish A. japonicus has the white marking extending from the eye down to the mouth. A. japonicus also has a red stripe on its dorsal fin that is lacking on the Gold-rimmed Tang. Both these fish are delicate when first acquired and can be difficult to acclimate to the aquarium. The Gold-rimmed Tang, A. nigricans, is fairly easy to care for once it’s settled, while A. japonicus is more difficult to sustain in captivity. A. japonicus is also less frequently available.
The Gold-rimmed Tang is relatively small in size, reaching about 8 1/3 inches (21.3 cm) in length, but it’s a great consumer of algae growing in the home aquarium. It can be a great choice for a mini reef, but despite its size, it is a more aggressive surgeonfish and needs a larger tank than other similarly sized tangs. It is also a fairly high maintenance fish, making it best suited for intermediate aquarists. It needs a minimum sized tank of 125 gallons to give it plenty of room to swim. It can generally be kept in a community with a variety of tank mates, but it can get aggressive towards other fish with a similar body shape and diet. It is also aggressive to others of its own genus, so should be kept singly.
- For more information on keeping saltwater fish see: Marine Aquarium Basics: Guide to a Healthy Saltwater Aquarium
Gold-rimmed Tang – Quick Aquarium Care
|Aquarist Experience Level:
|Minimum Tank Size:
|125 gal (473 L)
|Size of fish – inches:
|8.4 inches (21.31 cm)
|72.0 to 78.0° F (22.2 to 25.6° C)
Habitat: Distribution / Background
The Gold-rimmed Tang Acanthurus nigricans was described by Linnaeus in 1758. They are found across a wide range in the Indo-Pacific: in the Eastern Indian Ocean from Cocos-Keeling Islands and Christmas Island; the Pacific Ocean from the Ryukyu Islands and the Great Barrier Reef to Japan and Hawaii, and the French Polynesia (excluding Rapa); and across the Pacific Ocean at the Revillagigedo Islands, Cocos Island, Galapagos Islands and Mexico.
The genus name Acanthurus means “thorn tail,” and the species name nigricans comes from Latin for “blackish.” This species is listed on the IUCN Red List of Threatened Species as Least Concern (LC) due to it being widespread throughout the Pacific Ocean. It is common and abundant throughout most of its range and occurs in a number of marine reserves. Interestingly, in the wild, this is the second most numerous fish in areas around American Samoa.
The common names they are known by describe their color and the duties performed by their sharp retractable tail area spines. These include Gold-rimmed Surgeonfish, Gold-rim Tang, Golden Rimmed Surgeonfish, Goldrim Surgeonfish, Gold Edge Tang, Yellowrimmed Surgeonfish, Whitetail Surgeonfish, Yellow Spotted Surgeonfish, Yellow-fin Tang, Black Surgeonfish, Blackear Surgeonfish, Gray Surgeonfish, Powder Brown Tang, Velvet Tang and Velvet surgeonfish.
It is also referred to as the Whitecheek Tang, Whitecheek Tang, Powder Grey Tang, Whiitecheek Surgeonfish, and White-cheeked Surgeonfish in the aquarium trade. The name Whiteface Surgeonfish is sometimes used when referring to this species, but this is actually a common name for A. japonicas, since the Gold-rimmed Tang only has its white areas limited to below the eye and a band around the mouth.
About the Acanthurus Genus:
This species is a member of the Acanthuridae family of Surgeonfish. It belongs to the subfamily Acanthurinae as a member of the Tribe Acanthurini, in the large Acanthurus genus. Acanthurus is the type genus of the Acanthuridae family and there are currently 38 recognized species in this genus. Containing almost half of the currently 82 Surgeonfish species, this is the largest genus in the family.
Acanthurus are found in the tropical, subtropical, and some temperate waters of the Atlantic and Pacific. The majority of the species occur in the Indo-Pacific Oceans but there are 5 species found in the Atlantic Ocean. The Western Atlantic is home to four of these; the Blue Tang SurgeonfishA. coeruleus, DoctorfishA. chirurgus, Ocean Surgeon A. bahianus, and the Gulf Surgeonfish A. randalli; with the Monrovia Doctorfish A. monroviae occurring in the Eastern Atlantic.
Surgeonfish usually live in large schools or in pairs. Coastal waters, harbors and even estuaries for the young are prime areas for many of these fish. They feed during the day, but at night they sleep in small caves or crevices in the reef.
Typical of their family, many Acanthurus species occur in relatively shallow waters. The clear water and good sunlight promotes lots of algae growth on the rubble, rocks and coral skeletons for the herbivorous species to browse on. Those that are detritivores also occur here, feeding on detritus and diatoms from the substrate, often ingesting sand in the process. Some of the detritivores are also specialized for eating the feces of carnivorous fish. The smallest group of Acanthurus species, the zooplanktivores, swim in the open water feeding on miniscule prey.
Many members of the Acanthurus genus are very colorful, making them popular aquarium inhabitants. On average the species range from small species, such as the Brown surgeonfishAcanthurus nigrofuscus at 8 1/4 inches (21 cm), to the large Yellowfin SurgeonfishAcanthurus xanthopterus reaching up to 27 1/2 inches (70 cm). The smaller Acanthurus species can be kept in a good sized home aquarium but the larger fish, though often featured in public aquariums, are not really suitable for most hobbyist’s tanks.
Acanthurus species are often very territorial towards conspecifics in the wild, fiercely defending their area and foods. In the aquarium the attitudes of individual species vary, but they all tend to be aggressive towards their own kind. Some will bully other types of Surgeonfish as well, especially if added after the resident Acanthurus is established, There are even a few “bad boy” species that get so aggressive in the aquarium that they will dominate the tank, attacking all other fish. These tangs are best kept singly in most aquariums, with some possible exceptions when the tank is very large.
About the Gold-rimmed Tang:
In their natural habitat the Gold-rimmed Tangs are found at depths of at least 220 feet (67 m), but can be found as shallow as 6 feet (2 m). They occur along outer reefs from the surge zone downwards. Small juveniles are found hiding among large corals. Adults like exposed shallow rocky reefs, deep rocky walls and are found over rocky substrates as well as areas with sandy and coral substrate. They are also found in coastal areas, clear lagoons, and seaward reefs that have rocky and coral bottoms of the lower surge zone.
The Gold-rimmed Tang is a member of the Acanthurus achilles species complex that hybridize when their distributional ranges overlap each other. This complex also includes the Achilles TangAcanthurus achilles, the Powder Blue TangAcanthurus leucosternon, and Powder Brown TangAcanthurus japonicus (also called the White-faced Surgeonfish). The Gold-rimmed Tang has been known to hybridize with all three other members of this complex.
They co-occur with the Powder Brown Tang A. japonicus in southern Japan and the Bonin Islands, where they are known to hybridize. A. japonicus is very similar in coloring, however on its face it has white running from the eye down to the mouth rather than just a patch under the eye. Due to their similar appearance, A. japonicus was once even considered a subspecies of the Gold-rimmed Tang, with the name japonicus referring to its Japanese locality. Both these fish are sold as a “Powder Brown Tang,” but the Gold-rimmed Tang is a little more hardy than A. japonicus.
Gold-rimmed Tangs are territorial and solitary, rarely forming groups. Juveniles are typically found alone, however adults tend to form monogamous relationships when spawning, and at that time they can be found alone or in groups. They are considered herbivores because they graze on algae lawns in the wild. As grazers, they primarily consume various algae and detritus, but may inadvertently pick up small crustaceans. They feed on filamentous algae, detritus, and several benthic algae and weeds. These include species of Caulerpa, Cladophora, Codium, Dictyata, Gracilaria, Laurencia, Padina, Polysiphonia, Turbinaria and some unidentified algae.
- Scientific Name: Acanthurus nigricans
- Social Grouping: Varies – Primarily occur singly, though are monogamous when spawning, and then can be found alone or in groups.
- IUCN Red List: LC – Least Concern
The Gold-rimmed Tang is deep bodied with an oval disk shape. On each side of the caudal peduncle (base of the tail fin) is a single spine or â€œscalpelâ€ used for defense or dominance. When not in use the spine is folded down into a groove. It has a continuous dorsal fin and a slightly protruding mouth to get at algae between rocks.
Females can reach up to 8.39 inches (21.3 cm) in length, with males being slightly smaller. Tangs grow to 80% of their total length within the first 4 to 5 years, so these fish will reach about 6.75″ in that amount of time. Like other tangs, they have an expected life span of 30 to 45 years (Choat and Axe 1996), though possibly less in captivity.
The adult Gold-rimmed Tang has a brownish to black body with a white patch from just under the eye and a narrow white band nearly encircling the mouth. The dorsal, anal, and ventral fins are black and edged with a beautiful blue. There is a yellow stripe running along the body just above and below the dorsal and anal fins that broadens towards the back, extending almost all the way across the lateral portion of the fins. The caudal fin is whitish, shading into a pale blue, with a vertical yellow bar just inside the back edge of the fin. On each side of the caudal peduncle is a single yellowish spine or â€œscalpelâ€ used for defense or dominance.
This species and the White-faced Surgeonfish A. japonicus are two very similar looking fish that both claim the title of “Powder Brown Tang.” Both have a very similar appearance overall, in body and fin colorations, and both have white on the face. A close observation is needed to distinguish them. The primary difference, represented by their common names of “White-faced” and “Whitecheek” is the extent of the white on the face. The Gold-rimmed Tang (Whitecheek Surgeonfish) has just a white patch under the eye this same patch extends down to the mouth on the (White-faced Surgeonfish) A. japonicus.
There are some other markings that distinguish these two as well. The White-faced Surgeonfish A. japonicus has a red band along the back of the dorsal fin and a yellow spot just under the pectoral fin, both of which are missing from this species. But the Gold-rimmed Tang has a yellow band on the back third of the caudal fin that is missing on A. japonicus . Also on the Gold-rimmed Tang, the brown coloration tends to extend over the entire body to the tail fin, while it fades into a yellowish color towards the back on the White-faced A. japonicus. Lastly, a not so noticeable difference is that A. japonicus has a more oval shaped body.
- Size of fish – inches: 8.4 inches (21.31 cm) – Females are larger than males.
- Lifespan: 30 years – In the wild surgeonfish can typically live 30 to 45 years, possibly less in captivity.
Fish Keeping Difficulty
The Gold-Rimmed Tangs are delicate fish when first obtained and can be difficult to acclimate. Though it is unknown exactly why, it is possibly related to stress induced during collection and shipment. They are also initially quite shy and need lots of nooks and crannies in rocks/ corals to hide in to feel secure. Offer lots of marine algae, a really good macro algae to get them eating initially like gracilaria is a good idea as most tangs can’t resist it. Other good algae are Japanese Nori, kombu, and spirulina. Once they can adapt to a captive environment if given the right habitat, tank size, and tank mates.
Once acclimated they are moderate to care for and are suggested for intermediate aquarists. They are generally hardy and can handle a wide range of water parameters once they get settled. However, they will do best in an environment that provides consistency, not only in water conditions and quality, but also in decor and fellow inhabitants. Being territorial and high strung, they can easily stress and become ill when kept with aggressive tangs or housed in smaller tanks, under 125 gallons.
To maintain this tang will require top quality water conditions and close attention to a proper diet. It is susceptible to bacteria resulting from organic buildup which deteriorates water quality. Consequently it will need vigorous filtration, protein skimming, and regular small water changes. Being a voracious algae eater, a good algae growth in the aquarium helps provide for its nutritional needs as well as making it an excellent candidate for a reef environment. If kept with carnivorous fish it may not get the vegetables it needs, possibly suppressing its immune system. Feed your Gold-rimmed Tang first so they are full of good vegetable foods and less likely to eat meaty foods.
All Surgeonfish are wild caught and newly imported tangs can suffer from a mix of internal and external parasites, poor handling and housing, and a lack of nutrition. When selecting your fish, for the best success in keeping it long term, there are a few important things to consider. Make sure it has been in captivity for a while, it should be lively and actively picking at the decor. The coloring should be good and in shape, a pinched stomach is not necessarily a problem and can often be resolved with a good feeding regime. But be cautious if the upper body behind the eyes is sunken in when viewed from the front.
All Tangs should be isolated, quarantined for a couple of weeks after purchase so they can rest up. This also gives you an opportunity to observe and treat them for possible diseases before introducing them into your main system. They are susceptible to nutritional disorders which may cause color loss and Head and Lateral Line Erosion HLLE (called Hole-in-the-Head Disease in other species). Avoid activated carbon, as it is thought to be linked to HLLE.
These tangs can be housed in a fish only tank or in a reef environment as they will not harm corals. They are best kept as the only tang in the tank and the tank should be located in a calm part of the home to help keep stress levels low. Make sure there are plenty of crevices for the fish to hide in to feel secure. They need to be well fed, at least 3 times a day, with a variety of vegetable foods and some meaty foods, along with good algae growth in the aquarium, or algae sheets available for their constant grazing. Some successful aquarist have noted that they are best kept in a reef like setting rather than a fish only community.
Caution needs to be exercised when handling surgeonfish as a cut from its scalpel can cause discoloration and swelling of the skin with a high risk of infection. The pain lasts for hours then still ends up having a dull ache. When capturing your tang, use a container, not a net, due to the various spines they have on their tail, anal and pelvic fins.
- Aquarium Hardiness: Moderately Difficult
- Aquarist Experience Level: Intermediate – Suggested for the intermediate aquarist, as it is difficult to acclimate and moderately difficult in care.
Foods and Feeding
Although they are omnivores, the diet of the Gold-Rimmed Tangs is primarily that of an herbivore. In the wild they feed almost exclusively on filamentous algae, diatoms and weeds and algae, but will also ingest some small crustaceans as they feed. They are continuous feeders and they need to be provided a proper diet. In the aquarium the majority of their intake will be vegetable matter. Provide lots of marine algae, prepared frozen formulas containing algae or spirulina, and flake or pellet foods with spirulina. Only feed frozen brine and mysid shrimp sparingly.
Having an aquarium with good algae growth, or providing a piece of Japanese Nori, kombu, or other seaweed is essential to satisfy their constant grazing requirements. Seaweed sheets can be affixed to a rock with a rubber band, or alternatively, it can be adhered to the aquarium glass with a vegetable clip. Until they become quite comfortable, however, they may not feed from a clip. Live rock with micro and macro organisms will also be greatly appreciated. Some hobbyists also report success with supplemental foods such as previously boiled or frozen zucchini, broccoli, spinach, and leaf lettuce.
Providing a vitamin supplement (including vitamin C) can help provide for their nutritional needs and help fend off disease. Dried pellets can be soaked with liquid vitamins, vitamins can be added to the food, or liquid vitamin can be added into the water.
To get them eating initially, offering a really good macro algae initially, like gracillaria, is a good idea as most tangs canâ€™t resist it. Culturing macro algae in the tank, like chaetomorphia, for ongoing maintenance is also good. They are not too picky about foods once they get settled. Feed 3 times a day in smaller amounts instead of a large quantity once a day. As continuous grazers, they will benefit from this and it will also keep the water quality higher over a longer period of time.
- Diet Type: Omnivore – These fish are primarily algae grazers, but will inadvertently pick up some small crustaceans living in the algae.
- Flake Food: Yes – The food should have Spirulina in it.
- Tablet / Pellet: Yes – The food should have Spirulina in it.
- Live foods (fishes, shrimps, worms): Some of Diet – If the fish is not eating, offering live mysis or brine shrimp, gut-loaded with spirulina flake, may initiate a feeding response.
- Vegetable Food: Most of Diet – Feed your herbivorous fish first.
- Meaty Food: Some of Diet – Only a very small amount of its diet. In a reef tank, copepods will be ingested with naturally growing algae, and supplementing may not be necessary.
- Feeding Frequency: Several feedings per day – They need at least 3 feedings a day along with algae sheets affixed to rocks for their constant grazing in between feedings.
The Gold-Rimmed Tang needs a lot of food, so there is a large bio-load on the aquarium. A large tank is important for this tang with clean, stable water conditions, and a smaller tank will foul quickly. Surgeonfish, in general, are not as forgiving as some other fish when it comes to water quality. Regular water changes done bi-weekly or monthly will help replace the trace elements that the fish and corals use up. A suggested guideline is to keep up with your water testing, which will tell you when your tank needs a water change.
- Fish only tanks:
- Large Tanks 125 gallons and over, once water is aged and stable, can be changed 15% bi-weekly to 30% monthly, depending on bioload.
- Reef tanks:
- Large Tanks 125 gallons and over, once water is aged and stable can be changed 10% bi-weekly to 20% monthly, depending on bioload.
For more information on maintaining a saltwater aquarium see: Saltwater Aquarium Basics: Maintenance. A reef tank will require specialized filtration and lighting equipment. Learn more about reef keeping see: Mini Reef Aquarium Basics.
- Water Changes: Bi-weekly – Water changes of 10% every 2 weeks in a reef setting, with 15% bi-weekly to 30% monthly in a fish only tank.
The Gold-Rimmed Tang can be kept in a fish only tank or a reef environment. Like with other surgeonfish, the tank should be at least 6 months old so it is stable and established. This aging of the tank is necessary to provide your tang with stable water parameters and plenty of natural algae growth before adding your Gold-rimmed Tang. This fish is very active, always on the go, and constantly picking at algae on the decor. A minimum sized tank of 125 gallons is suggested, but they usually do better in larger aquariums because they need lots of room to swim. A larger tank that is 6 feet long is even better for their deep-bodied shape and swimming needs.
They will swim in all levels of the tank, but need open areas on the upper levels to swim with no obstructions. The mid to lower areas of the tank should be well decorated with rocks and/or corals. To feel secure they also need many nooks and crannies to hide in and to wedge themselves into at night for sleeping. They thrive well in tanks with algae, and this decor will lend itself to algae growth. This fish will not bother corals or invertebrates so it highly useful in a reef environment. However keep corals glued down, as their quick speeds may topple a coral or two.
Tangs produce a lot of waste, so the larger the tank, the easier it is to keep clean. A strong skimmer and good filtration is recommended for long term health. Water movement should be strong. Surgeonfish need an aquarium with plenty of aeration and they love to have the water rushing over their gills at times. A strong current will also help provide good oxygenation. Any substrate is fine, though a sandy substrate to allow them to â€œblowâ€ the sand with their mouth when searching for foods. Moderate lighting is also fine, yet a stronger lighting will help encourage algae growth. When kept in a reef all factors need to be considered more specifically for the needs of the coral.
They swim non-stop, so do better with a little lower temperatures that also provide more oxygen. Their temperature range should range between 72-78Â° F (22-26Â°C). Long term exposure to temperatures of 79-83ËšF, according to some experts, may prove detrimental over 4 or 5 months time. They do well at the normal ocean salinity of 1.023 and a pH between 8.1 and 8.4, however both of these qualities, especially the pH should be stable. Avoid activated carbon, since this may be linked to Head and Lateral Line Erosion (HLLE).
- Minimum Tank Size: 125 gal (473 L) – Should be 6 feet long. Smaller tanks will cause more aggression and behavioral problems.
- Suitable for Nano Tank: No
- Live Rock Requirement: Typical Plus Hiding Places – Hiding places are needed to help reduce stress and for them to hide in at night. However, allow open upper areas for them to swim that are void of rock.
- Substrate Type: Any
- Lighting Needs: Moderate – normal lighting – Lighting is needed to provide algae growth on live rock. It can be kept under normal lighting conditions in the aquarium, but can also be kept under very bright light as long as some dimly lit spaces are provided.
- Temperature: 72.0 to 78.0Â° F (22.2 to 25.6° C) – Lower temperatures help provide higher oxygen levels, which is much needed for these active swimmers.
- Specific gravity: 1.023-1.025 SG
- Range ph: 8.1-8.4
- Brackish: No
- Water Movement: Strong – Good current and well oxygenated.
- Water Region: All – This fish will swim all over the aquarium, spending time in the open water and darting in and out of the rocks and coral. It will sleep in crevices in the rock work at night.
The Gold-rimmed Tang can be kept in either a community fish tank or a reef. It is semi-aggressive, but is one of the more aggressive surgeonfish. It can generally be kept in a community tank with a variety of tank mates, but it can get aggressive towards other species with a similar body shape and diet. It is peaceful towards other non tangs and does great in a community tank, however fish added after it may be picked on. It may get along with tangs from other genera that are a different color, have a different shape, and eat different foods, but only if the tank is hundreds of gallons. It is also aggressive to others of its own genus, so should be kept singly.
This tang will not bother any peaceful fish, small or large, and does well with smaller semi-aggressive fish like clownfish. It will not bother even the smallest, most peaceful goby, blenny or other peaceful fish.They ignore anthias, fairy and flasher wrasses and even large peaceful fish. Small dwarf angelfish that are more mellow, like the Coral Beauty should also be fine.
Aggressive tangs like the Sohal Tang, Triggerfish, Puffers and other larger and more aggressive fish should be left out of the equation when putting tank mates together. Avoid even smaller aggressive fish including dottybacks and aggressive clowns like Maroon Clownfish, unless the tank is hundreds of gallons, especially if your tang is a small juvenile.The key is a stress free, reef environment (or fish only with good lighting to provide algae growth) with no competition for foods from other herbivores.Large angelfish should not be housed with your Gold-rimmed Tang unless they are planktivores, who will not complete for vegetable foods.
The great thing about this tang, is that it is fine in a reef setting with corals, and it will graze on the algae. Just be sure to glue the corals down so your tang’s “burst of energy” does not dislodge them. A Gold-rimmed Tang may nip at Large Polyp Stony Corals (LPS) if they are not well feed.. At times this “nipping” at LPS is just the tang picking at the algae at the base of the coral, which is a great service to the coral!
Invertebrates are not at risk, however, a copepod or amphipod may be eaten here or there while the tang grazes on the algae in which they live. On a rare occasion, an occasional tang will find the slime that clams produce quite tasty. While the tang is not biting the clam, the action causes the clam to close often, stressing the clam and eventually this stress will kill the clam. This shouldn’t be a problem with a well fed tang.
- Venomous: No
- Temperament: Semi-aggressive – Though semi-aggressive, it is peaceful toward non-tang fish that do not share similar foods.
- Compatible with:
- Same species – conspecifics: Sometimes – Only possible exceptions are in a the tank is very large (10 feet long), 2 juveniles from different Acantharus species that do not look alike in color, and they are added at the same time.
- Peaceful fish (gobies, dartfish, assessors, fairy wrasses): Safe
- Semi-Aggressive (anthias, clownfish, dwarf angels): Safe
- Monitor – May be too aggressive, however in a much larger tank, should be okay.
- Large Semi-Aggressive (tangs, large angels, large wrasses): Monitor – Do not house with other Acanthurus. If adding other genera of tangs, the tank should be over 300 gallons. Only keep it with large angelfish that are planktivores. Large wrasses will not bother your Tang, however the constant swimming may stress your tang out.
- Large Aggressive, Predatory (lionfish, groupers, soapfish): Threat – Too stressful on this tang.
- Threat – Seahorses and most pipe fish need their own tank. Mandarins will not be bothered.
- Anemones: Safe
- Mushroom Anemones – Corallimorphs: Safe
- LPS corals: Monitor – Should not bother LPS if well fed.
- SPS corals: Safe
- Gorgonians, Sea Fans: Safe
- Leather Corals: Safe
- Soft Corals (xenias, tree corals): Safe
- Star Polyps, Organ Pipe Coral: Safe
- Zoanthids – Button Polyps, Sea Mats: Safe
- Sponges, Tunicates: Safe
- Shrimps, Crabs, Snails: Safe
- Starfish: Safe
- Feather Dusters, Bristle Worms, Flatworms: Safe
- Clams, Scallops, Oysters: Monitor – A rare tang will nibble on the slime clams produce, causing the clam to close and stress. However a well fed tang shouldn’t bother them.
- Copepods, Amphipods, Mini Brittle Stars: Safe
Sex: Sexual differences
In this genus, males are smaller than females.
Breeding / Reproduction
The Gold-Rimmed Tang has not yet been bred in captivity. Surgeonfish are a challenge to breed and rear in captivity. Successful breeding could only be accomplished in a very large display aquarium, and the larvae have proven very difficult to rear. Most home aquarists will not have a tank large enough to encourage spawning with surgeonfish.
For the last couple of decades there have been efforts in French Polynesia to collect the larvae of some species as it settles, and then rear the young. Also breeding a few species such as the Yellow TangZebrasoma flavescens, Regal TangParacanthurus hepatus, and the Naso TangNaso lituratus has been attempted. But neither of these methods have had sufficient success for commercial production. The difficulty starts after the eggs hatch. In the pelagic larval stage they are very small and easily damaged, followed by a very long planktonic larval stage, and then the fry are very slow growing.
The females of the genus Acanthurus are larger than males. They are open water spawners and form pairs. These pairs seem to stay together even within groups. The male may exhibit color changes during spawning to attract female and to warn rival males. If they are in a large school, a pair will break away and rise upward toward the surface and release their gametes.
These little floating fertilized eggs are spherical and have a single oil globule to aid in their buoyancy and dispersal. Each egg measures around 0.17 mm in diameter. Once they hatch, the larvae look like little kites with a long snout with a small mouth, and they stay in this state for 42 to 68 days. During this time, they fall prey to fish and other marine animals. Once they reach around 1 inch, give or take (23 to 33 mm), the larvae are then changed into the juvenile stage. Once they are ready to join the reef, the larvae settle out of the water column and develop into these 1â€ juveniles, seeking the protection and food sources of the reef and seagrass habitats.
Each egg measures around 0.17 mm in diameter. These little floating fertilized eggs are spherical and have a single oil globule to aid in their buoyancy and dispersal, thus making them pelagic. Once they hatch, the larvae look like little kites with a long snout with a small mouth, and they stay in this state for 42 to 68 days. During this time, they fall prey to fish and other marine animals.
Once they reach around 1 inch, give or take (23 to 33 mm), the larvae are then changed into the juvenile stage. The juveniles leave the water column and seek the protection and food sources of the reef and sea grass habitats. See the description in the Breeding Marine Fish: Tangs for more about how they reproduce in the wild.
- Ease of Breeding: Unknown – Surgeonfish are difficult to rear, yet some progress is being made in captivity.
The Acanthurus species are generally hardy once acclimated. However they do need a proper environment and tankmates, and the water quality needs to be pristine and stable, or they can suffer any disease that captive saltwater environments have to offer. They will succumb to illness quickly in a less than optimal environment. Common ailments include bacterial diseases, Head and Lateral Line Erosion HLLE (called Hole-in-the-Head Disease in other species), and parasitic infections such as protozoas (including Cryptocaryon), worms, etc.
Although they can be quite durable, Surgeonfish are prone to skin diseases. They produce less body slime than other saltwater fish and have been termed â€œdry skinnedâ€ fish by some. This makes them susceptible to Marine Ich or White Spot Disease Cryptocaryon irritans and Marine Velvet or Velvet Disease Oodinium ocellatum. Both of these are parasites. Surgeonfish are also susceptible to nutritional disorders which may cause color loss and HLLE (head and lateral line disease) which may be caused by poor water quality, unsuitable habitat conditions, lack of endogenous (internal) vitamins, and activated carbon.
Symptoms of Marine Ich are constant scratching, culminating with lots of white dots. Some refer to them as “Ich Magnets” because they are the first fish to exhibit signs of illness. Marine Ich results in the fish suffocating from the parasites blocking their gills, keeping them from providing oxygen. Marine Velvet is a parasitic skin flagellate. Symptoms are a peppery coating giving a yellow to light brown “dust” on body, clamped fins, respiratory distress (breathing hard as seen as frequent or quick gill movements), cloudiness of eyes, glancing off decor or substrate, and possible weight loss.
In the wild a cleaner wrasse (Labroides spp.) will help them by taking parasites from their bodies, however these wrasses are extremely difficult to sustain in captivity. Alternative fish such as Neon Gobies (Gobiosoma spp.) or cleaner shrimp can help them by providing this cleaning service in the home aquarium.
For treatment in captivity, the best routine is a quarantine tank. Provide a stress free environment with good quality foods, places to hide, and a quiet area for the aquarium. For external parasites you can slowly increasing the temperature of your tank to at least 82Â° F (28Â° C). That will prevent the parasite from completing its life cycle which includes the attachment to fish. A further combination of the higher temperatures with medicated food will provide timely relief.Some tangs are sensitive to copper because they have an important microfauna in their digestive system, so prolonged or continuous use of a copper treatment is not advisable. It is also said that pellets soaked in garlic may help fend off Marine Ich.
Parasites on marine fish kept with live rock or in any type of reef environment can be extremely difficult to treat. Typical treatments like copper and formalin solutions, as well as quinine based drugs are harmful to other marine creatures. However drugs such as metronidazole provide an effective and safe treatment for several protozoan and anaerobic bacterial diseases. Metronidazole works by ceasing the growth of bacteria and protozoa. Metronidazole is an antibiotic for anaerobic bacteria with anti-protozoal properties. This drug is reef safe, and medications are either added to the water or mixed with the fish food. Some available products that contain metronidazole include Seachem Metronidazole, Seachem AquaZole, Thomas Laboratories’ Fish Zole and National Fish Pharmaceutical’s Metro-Pro.
Providing a vitamin supplement (including vitamin C) can help provide for their nutritional needs, and vitamin C can help reduce Lateral Line Erosion (LLE). Enriching foods can be done by soaking dried pellets with liquid vitamins or adding vitamins to frozen and fresh foods. Although somewhat less effective, adding a liquid vitamin into the water can also work. Some hobbyists also report success with supplemental foods such as previously boiled or frozen zucchini, broccoli, spinach, and leaf lettuce. Some hobbyists also report success with offerings of supplemental foods such as previously boiled or frozen zucchini, broccoli, spinach, and leaf lettuce. For more information on diseases that saltwater tangs are susceptible to, see Aquarium Fish Diseases and Treatments.
The Gold-rimmed Tang, also called the Whitecheek Tang or Whitecheek Surgeonfish, is moderate to moderately expensive, depending on size. They are often available online and in stores, and it may also be possible to special order one.
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