Knight Goby (Stigmatogobius sadanundio)

Knight Goby

Last updated on September 3rd, 2022 at 11:50 pm

The Knight Goby, Stigmatogobius sadanundio, also known as the Fan Dance Goby, is an incredibly unique fish that has many characteristics that make it stand out from other gobies. These include the colors of its body, the way it moves, and even its physical appearance when it’s being prepared to mate during its fan dance behavior.

It is one of the most stunning species of goby available to the marine aquarium hobby. These small fish inhabit both inshore and offshore waters with substrates consisting of sand, rubble or mud bottoms, typically at depths of 1 to 20 meters (3 to 65 feet).

They are very popular in saltwater and freshwater aquariums because of their unique fan-shaped pelvic fins that they use to attract food and mates by looking like an injured or dead fish to the eyes of their prey, making them easy to catch.

If you are considering keeping this lovely fish in your marine aquarium, read on to learn more about their captive care needs.

Origin and descriptions

Knight Goby

The Knight Goby is a freshwater fish that originates from Central Africa. Although, it can also be found in Australia, Asia, and Madagascar. It has many names such as Sadanundio and Fan Dance Goby. Its common name, Knight Goby, comes from its unique behavior of fighting like knights for territory. They usually live in pairs or small groups with other Knight Gobies.

This species prefers to live in freshwater aquariums at temperatures between 74-82 degrees Fahrenheit with plenty of rocks, driftwood and caves to hide in. Their diet consists of most fresh foods but they prefer meaty foods like bloodworms, brine shrimp, daphnia, and tubifex worms.

Species profile

Knight Goby belongs to the family Gobiidae. This fish is also known as Fan Dance Goby, Knight Fish, Knight goby, and Stigmatogobius sadanundio. It can be found in the marine and brackish waters of the Indo-Pacific region. Its body is oval in shape with a pointed snout and large eyes.

Pelvicachromis Pulcher (Kribensis Cichlid)

The coloration of its body varies from brown to orange depending on its habitat. Knight Goby feeds on worms, crustaceans, mollusks and other small invertebrates.

It grows up to 4 inches long in nature but they are smaller when kept as pets. These fishes are very peaceful and cannot survive alone so they should always be kept in groups of at least six individuals. They should not be kept with aggressive species like tiger sharks or angelfish because they will eventually get killed by them.

Scientific name

The scientific name of the Knight Goby is Stigmatogobius sadanundio


The Knight Goby is primarily a reef-dwelling fish, as they need hard substrate like rocks or coral to survive. They are also known to burrow into marine sand if necessary. As far as water temperature goes, they prefer warm waters and can live in both saltwater and freshwater environments. Reefs with lots of algae growths make good homes for these fish because it helps them hide more easily from predators.

Knight goby size

Knight Goby

The Fan Dance Goby (knight Goby) can grow up to size around 4 inches (10 cm) in total length.

Tank size

The minimum recommended tank size for Knight Goby is 20 gallons (76 liters) or larger tanks.

Tank requirements

Knight gobies are freshwater fish that can grow up to 10 cm in length. Aquariums should be well-planted with hardy, fast-growing plants and have plenty of live rock to provide hiding places and a source of food. Knight gobies have poor eyesight, so they rely on senses of smell and vibration to navigate their environment.

They prefer tanks with plenty of hiding places, so you’ll want to use rocks and driftwood for them to swim through and under. Since they’re labyrinth fish, they require access to both fresh and saltwater; you’ll need two separate filters for their tank—one for freshwater, one for saltwater—and an air pump that will push water from one side of their tank into another as part of their daily routine.

Mono argentus (Silver Moony Fish)

You’ll also need to keep track of their diet: they eat mostly meaty foods like worms, brine shrimp, and bloodworms.

Tank mates

They can be kept in a community tank with other schooling fish like kuhli loaches and guppies, but should never be housed with long-finned or aggressive species like bettas, gouramis or barbs.

Other species that will do well with knight gobies are Skunk Goby, Mono Sebae, Target Fish, Mono Argentus, Bumble Bee Goby, Archer Fish, Butterfly Leaf Goby, Indian Glassfish, Silver Scat, Green or Orange Chromide, American Flagfish, and Red Scat.

Knight Goby breeding

Knight Goby

In tropical brackish water fish keeping, breeding Knight Goby is among the most challenging tasks. The knight goby’s territorial nature makes the task more difficult, as does the static nature of the aquarium. You are a skilled tank keeper indeed if you manage to breed your knight gobies.

Changing the temperature and increasing the salinity of the water are two ways to encourage breeding.

The water should be warmed to 75–82 °F (24–28 °C) using a standard aquarium heater in order to help your knight gobies get into the breeding zone. Whatever the type of tank you have, you may want to modify the salinity to between 14 and 1.005SG or marine strength. Fish in estuaries will spawn when the water’s salinity decreases. Increase the ratio of freshwater if you normally keep a brackish aquarium.

They are shelter spawners. When the female has finished courting, she will lay eggs on the ceiling of the shelter you have put up for them. Breeding pairs can lay up to 1,000 eggs.

While doing a deep clean on the tank, be careful not to disturb the filmy strings. When the eggs hatch, the male knight goby abandons their parental duties. Knight gobies will try to eat the fry if they are in the tank with other knight gobies.

Reedfish, Rope Fish (Erpetoichthys calabaricus)

As soon as the eggs hatch, the fry should be transferred as soon as they reach a catchable size. You can feed the fry of knight goby fish brine shrimps or sinking flakes.

Are they aggressive or peaceful?

The Knight Goby is generally peaceful and can be kept with other fish of similar size. However, they will likely pick on slow or ill fish, so take care to give your Knight Goby a healthy tankmate or two to keep its company. It’s fine to keep them in a community tank as long as there are no territorial species; they tend to do best when kept alone or with one other peaceful fish of comparable size.

Knight Goby Care

Knight Goby

The Knight Goby is one of several goby species that are commonly referred to as fan gobies or fan dance goby. This name is derived from their tendency to move in and out of specific areas of rockwork in a sort of dance as if they were performing for an audience.

Keeping them healthy, however, can be difficult due to their intolerance for copper and their need for large amounts of high-quality food. They’re also very shy fish with limited coloration and are best kept in tanks with lots of hiding places.

Given these requirements, we recommend keeping them in a tank of at least 20 gallons (76 liters) with plenty of live rock and open swimming space.

Knight goby diet

The Knight Goby is a carnivore by nature but will accept most meaty foods including frozen mysis shrimp, krill, bloodworms, brine shrimp, and other similar foods. They should be fed at least twice per day and have been known to eat small fish when well fed.


Knight goby can live for up to 3-5 years.

Parasites and diseases

Knight gobies are well-known for their fan dance behavior, but it’s a symptom of a disease called whirling disease. Whirling disease is caused by a parasite that targets fish brains and eyes. The parasite travels to your fish’s brain and makes them behave strangely—sometimes in ways that put them at risk of predation.

Pseudomugil signifer (Pacific Blue Eye Fish)

It also increases your fish’s metabolism, which means they need more food to survive. Eventually, if left untreated, the whirling disease will kill your fish. If you notice strange behavior or bulging eyes on your knight goby or other aquarium fish, contact an aquarium veterinarian immediately.


Knight gobies are in danger of predation by larger fish. To avoid becoming a meal, these fish often hide in caves and crevices, only coming out during low tide when there are no predators around.

Some common predators are rockfish, bass, flounder, and eels. The knight goby uses its camouflage to hide from these predators. The fan dance goby has been known to mimic other fish like flatfish in order to blend in with its surroundings. This is a very effective way for it to avoid being eaten by larger fish.

Do they make good pets?

Knight gobies do not make good pets for beginner aquarists and therefore should only be kept by advanced aquarists.

Knight gobies, while ideal for experienced fishkeepers, can be a challenging first saltwater aquarium pet. Despite their small size and peaceful demeanor, they require precise care and are extremely sensitive to environmental changes; common mistakes often result in early death.

Knight gobies are not reef safe and will eat small invertebrates in your tank, so they are a poor choice for a reef tank. If you still want to try one out though, keep it with peaceful bottom dwelling fish like snails or blennies.