Black Clown Goby (Gobiodon atricirratus)
The Black Clown Goby (Gobiodon atricirratus) known to tropical fish keeping enthusiasts as the Azure Goby or Black Goby, is native to the Western Pacific Ocean, with a wide distribution throughout the coral rich waters of Indonesia, the Philippines, and Melanesia.
Like all members of the Gobiodon genus, the Black Clown Goby is a cryptic, coral dwelling species that is found in shallow to moderate depths from 6 to 50 feet where they spend the majority of their lives perched among the protective branches of stony corals like Acropora and Stylophora that they utilize for shelter, as lookout posts, and as potential nesting sites.
Native to the Ceram Sea and broader Indo-Pacific, Gobiodon ceramensis which is the same species as Gobiodon atricirratus, are most commonly encountered alone, in pairs, or in small groups “hopping” from coral branch to branch and nesting among the polyps.
.The Black Clown Goby is a shy, peaceful, inquisitive, and less common relative to the Citrinis Clown Goby and Green Clown Goby. Because they are not strong swimmers and rarely venture into open water, they are usually spotted by divers as they “hop” from one Acropora branch to another, amongst the coral reefs of their range.
The Black Clown Goby is prized by many tropical fish keeping enthusiasts for their inquisitive demeanor, uniform dark colors, and diminutive size for small reef tanks.
Black Clown Goby (Gobiodon atricirratus)
The Black Clown Goby is a small, stout, blunt headed species that has a deep, velvety black, dark brown, to dark purple body color with subtile, lighter vertical stripes or spots. Their body lacks scales and is coated in a mildly toxic mucus that protects them for most predators.
The Black Clown Goby is best housed in a mature FOWLR or preferrably a well established reef aquarium of at least 20 gallon capacity with a live sand or fine coralline gravel substrate, plenty of live rock, and a healthy growth of branching stony corals (preferably Acropora or Pocillopora) for them to perch on, hide among and nest. A specialized host coral environment is essential for this species to truly thrive.
The Black Clown Goby is peaceful toward invertebrates and most other fish species but is highly territorial of their host coral and toward conspecifics. Gobiodon atricirratus should be housed as the only clown goby is a system unless the tank is large enough to provide separate, distinct host corals for each individual fish.
Although they are generally reef safe, the Black Clown Goby may aggressively nip at the polyps of their host coral to clear a small area for perching or nesting. This usually results in localized, temporary tissue recession on the coral.
Like many clown gobies, the Black Clown Goby has been successfully captive bred in an aquarium environment. Commercial aquaculture has occured but is less common for this specific species.
Black Clown Gobies are often hermaphrodites and form strong, monogamous pair bonds. When ready to breed, the pair will select a suitable spawning site, usually the underside of a branching coral like Acropora. Both the male and female will strip a small patch of coral tissue and meticulously clean the chosen area using their mouths and fins to remove algae, detritus, or anything else from the surface.
The female will lay a clutch of adhesive eggs, which are attached to the prepared substrate, deep within the branches of the coral. Immediately after the female lays her eggs, the male follows behind her and fertilizes them. The male vigorously guards the nest against potential predators while aerating the eggs with his pectoral fins and mouthing the eggs to remove any that are dead or infertile. The “mouthing” also prevents any fungus or disease from spreading through the mass of eggs.
The male tends to the eggs until they hatch out into small larvae. Depending on water temperature, the incubation period can last anywhere from a few days to a week. The tiny larvae are planktonic and drift along in the water column for a period before settling on the seafloor and developing into juvenile gobies. Under optimal conditions, spawning can occur as frequently as every few days.
In an aquarium environment, rearing the larval stage is challenging due to the minute size of the fry and their requirement for specialized live foods during the planktonic phase.
In their natural environment, the Black Clown Goby feeds primarily on zooplankton and a variety of microorganisms. In an aquarium environment, they are generally easy to feed but must be fed directly near it’s coral perch.
They are slow, deliberate eaters that will accept a varied diet of meaty and prepared frozen foods such as Mysis shrimp, vitamin enriched brine shrimp, Cyclops and Copepods, high quality marine pellets, and marine flakes. Small frequent 2 to 3 times a day feedings are recommended to ensure they receive adequate nutrition without being outcompeted by other fish in the tank.
Black Clown Goby (Gobiodon atricirratus or Gobiodon azeus) is occasionally available to tropical fish keeping enthusiasts from a variety of online retailers, wholesalers, and transhippers as wild caught specimens from the Western Pacific. They are generally less common than the Green or Yellow varieties.
Prices for the Black Clown Goby vary by retailer, area of collection, and size of fish but range in the area of $15.49 – $39.99.
Black Clown Goby (Gobiodon atricirratus)
Minimum Tank Size: 20 gallon (55 gallons for pairs)
Aquarium Type: Reef or FOWLR
Care Level: Difficult
Temperament: Peaceful
Aquarium Hardiness: Hardy when acclimated
Water Conditions: 75-81° F, dKH 8 – 12°, pH 8.1–8.4, sg 1.023-1.025
Max size: 1.5″-2″
Color Form: Black, Dark Brown, Dark Purple
Diet: Omnivore/Planktivore
Compatibility: Reef Safe with caution
Origin: Western Pacific Ocean
Family: Gobiidae
Lifespan: 4 – 6 years
Aquarist Experience Level: Beginner/Intermediate
