The Mandarin Goby (Synchiropus splen

Mandarin Goby (Synchiropus splendidus)

didus) known by various names to tropical fish keeping enthusiasts such as the Mandarinfish, Mandarin, Mandarin Dragonet, Striped Mandarin Fish, Striped Dragonet, Green Mandarin, and Psychedelic Goby is native to the Western Pacific Ocean including the Coral Triangle, Australia’s Great Barrier Reef, Hong Kong, Micronesia, New Caledonia, Taiwan, Japan, and Palau. Its range extends from the Ryukyu Islands south to the warmer waters of southern Australia.

The Mandarin Goby can be encountered alone, in pairs, but usually in small groups spread over small areas on the silty bottoms of the protected shallow lagoons and coral reefs of their range among corals and rubble, at depths from 3 to 60 feet, where they feed on small crustaceans and other animals found in the substrate.

The Mandarin Goby is a relatively peaceful, slow moving species that prefers slow moving water. Instead of scales, they have a thick, bitter tasting, unpleasant smelling mucous coating on their skin that protects them from predators and diseases.

Although they have a body shape that is similar to that of a goby, the Mandarin Goby is really a Dragonet.

Mandarin Goby (Synchiropus splendidus)

Synchiropus splendidus are brilliantly colored and have a broad, depressed head with red eyes and black pupils. They have a vibrant bright blue body color with broad, swirly, orange, red, and yellow stripes and a blueish green face with bold blue stripes. They have large pelvic fins that are often mistaken for pectoral fins, that are used for “walking” on the seafloor. Their pectoral fins are mostly transparent as are the anal fins and part of the tail. The rest of the fins are striped a vibrant orange and blue. Males are larger than females and have a large, tall, blue and orange striped dorsal fin. Synchiropus splendidus and the closely related Synchiropus picturatus are the only two vertebrates known to have a blue cellular pigment coloring.

Mandarin Goby (Synchiropus splendidus)

Different varieties exhibit different markings and colors. The red mandarin is the same species but the pelvic fins, normally orange, are red. The Spotted Mandarin has black, pink, and blue spots on a light gray green body. Rare individuals have a bright red brown body color and in some extremely rare cases, the entire fish is red with black stripes.

A single Mandarin Goby can be housed in a mature 30 gallon FOWLR or reef tank with a thick live sand substrate and plenty of active live rock for them to feed on and hide among. In order to keep a mated pair, at least a 60 gallon capacity tank packed with plenty of mature live rock for the fish to feed on and hide among is required.

Mature live rock populated with copepods is an essential food source for the Mandarin Goby.   At least 75 pounds of live rock is recommended to house one Dragonet.

When enough live rock is not provided for each individual, the fish will eat all the copepods on the rock and usually starve to death.

For that reason, adding a Mandarin Goby to a new setup without an established food supply is highly discouraged.

Mandarinfish in a FOWLR aquarium usually get along well with other non aggressive species of similar size and temperament such as the Coral Beauty, Firefish, Pajama Cardinal, etc.

Because the males are highly territorial, they cannot be kept in groups with their own kind.

Although Mandarin Goby larvae are among the smallest ever recorded at hatching, they have been bred in an aquarium environment.

Mandarin Gobies are pelagic spawners. In anticipation of the spawn, small groups of up to five male and female gobies will gather up after sunset.   A single male, usually the largest in the group will pair up with an available female to spawn. Spawning pairs will rise towards the surface in close contact with each other to release clutches of 12 to 205 small, colorless, spherical and pelagic 0.7 to 0.8 mm dia. eggs and sperm for external fertilization. The males create a funnel with their anal fin when releasing the sperm to insure successful fertilization. During the spawning ritual, males frequently mate several times during the night with multiple females, whereas the females can only spawn once per night. Because there seems to be a sexual preference by the females for larger males, the larger and stronger males mate more frequently.

Synchiropus splendidus larvae have a short incubation time and develop quickly. As the clumped together egg masses slowly break apart in the water column; about 36 hours after fertilization, the eyes become pigmented and the mouth becomes developed. After 8 to 11 days the fins become developed and the tiny larvae are active and feeding. After 12 to 14 days, the juveniles look like the adults with a large head and a triangular shaped body. In 18 to 21 days, the body turns a dark orange brown color with greenish banding and the dorsal spines can be observed. The adult color pattern does not develop until the second month when the fish are 10 to 15 mm. long.

Mandarin Gobies breed throughout the year with spawning occurring at weekly intervals for several months. They can double their populations in less than 15 months.

In their natural habitat, Mandarin Gobies feed throughout the day on small crustaceans and invertebrates that they find in the substrate. They have a mixed diet that includes fish eggs, harpacticoid copepods, polychaete worms, small gastropods, gammaridean amphipods, and ostracods.

In an aquarium environment Synchiropus splendidus have specific dietary requirements which is why many tropical fish keeping enthusiasts considered them difficult to keep.    Some individuals refuse to eat anything but live amphiopods and copepods but if they can be successfully acclimated to eating aquarium fare such as frozen copepods, baby brine shrimp, cyclops, and small mysis shrimp they are hardy and resistant to disease. A turkey baster or syringe can be used to target feed small portions directly onto the live rock or near the fish several times a day.

Most successful tropical fish keeping enthusiasts cultivate robust populations of copepods to feed their Mandarin Gobies by attaching a refugium to the sump in the tank. A mass of macroalgae such as chaetomorpha in the refugium allows the copepods to breed and multiply without being preyed on. Detritus and microfauna produced by the macroalgae provide shelter and food for the copepods. Robust copepod populations can also be cultivated by allowing the tank with ample live rock to mature for at least six months or so before adding fish.

The Mandarin Goby (Synchiropus splendidus) is readily available to tropical fish keeping enthusiasts as wild caught and aquacultured specimens from online retailers, wholesalers, and transhippers. Prices for approximate purchase sizes Small: 1″ to 1-1/2″; Medium: 1-1/2″ to 2-1/4″; Large: 2-1/4″ to 3″ vary from $ 29.99 for small specimens to $ 39.99 for large.

Mandarin Goby (Synchiropus splendidus)

Minimum Tank Size: 30 gallon (60 gallons for pairs)
Aquarium Type: Reef or FOLR
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: 3.5″
Color Form: Blue, Black, Green, Orange, Red, Yellow
Diet: Carnivore
Compatibility: Reef Safe
Origin: Western Pacific Ocean; Ryukyu Islands to southern Australia.
Family: Callionymidae
Lifespan: 5 – 20 years
Aquarist Experience Level: Intermediate/Expert