Not furry, but we like them anyway.

Niger Triggerfish

Odonus niger (Rüppell, 1836)

Also called Red-toothed triggerfish, Redtooth triggerfish, Blue triggerfish, Redfang triggerfish

SpeciesShort profile

From Indo-Pacific and Red Sea, from the East African coast east to the Marquesas and Society Islands, north to southern Japan and south to Australia's Great Barrier Reef.1 2

At a glance the quick version

Length30 to 50 cm1 2 3

Sizemedium

Commonly 23 to 30 cm; maximum recorded 50 cm total length. Aquarium specimens reach about 30 cm (12 in).

Rich blue to purple colouring

Hardy and easy to feed

Talks with audible grunts

2 3

Looks how to spot one

Scaled, deep-bodied triggerfish with a lyre-shaped tail

A sturdy, oval triggerfish whose body glows deep blue to purple, with a paler blue head and blue-green lines around the face. Its tail fin sweeps out into long upper and lower points like a lyre, and its small teeth are a striking red. Its colour shifts with mood, food and surroundings.2 1

ColoursDeep blue to purple bodyLight blue headBlue-green facial markingsRed teeth2

Personality what they are like

Among the calmer triggerfish when young, it grows bolder and more territorial with age. It suits a fish-only display with other sturdy, similarly sized fish.2 3

Daily activity how busy a day looks

An active swimmer that moves with a propeller-like rippling of its dorsal and anal fins. In the wild it patrols current-swept reef channels, so it appreciates open swimming room plus rocky caves to retreat into.2 1

Grooming and care the hands-on bits

Rated easy to care for. Keep it in a large fish-only aquarium with stable marine conditions; it may move rocks and decor around, so secure the aquascape.3

Home where they are happiest

A very large marine tank of at least about 680 litres (180 US gallons) with rock caves for shelter. Water about 22 to 26 °C, pH 8.1 to 8.4, dKH 8 to 12, specific gravity 1.020 to 1.025.3

Food basics what goes in the bowl

A meaty, varied diet such as squid, krill, clams, small fish and hard-shelled shrimp; the crunchy foods help wear down its continuously growing teeth. Wild fish eat zooplankton, sponges, crustaceans and some algae.3 1 2

Company who they like around

Can be kept singly with other robust, similarly sized fish. In the wild it gathers in large groups to feed on plankton, and pairs guard their nests together.1 2 3

The story where it all began

Eduard Rüppell described the species in 1836 from the Red Sea region. It is the sole member of its genus, and it has long been a popular aquarium fish, also caught in small local fisheries.1 2

Fun facts for the dinner table

1
Its red teeth are needle-sharp, with two prominent teeth in the upper jaw.2
2
It swims mainly by undulating its dorsal and anal fins rather than its pectoral fins.2
3
Only the female tends the eggs, but both parents stand guard over the nest.1
4
It can make grunting sounds.3
5
Large groups gather in open water above the reef to feed on zooplankton.1

Recognised by the official bits

IUCN Red List: Least Concern (assessed 13 January 2022)1
Taxonomy: Family Balistidae; the only species in the genus Odonus; described by Eduard Rüppell in 18362

The care rhythm Furry Diary remembers it for you

A typical home-care rhythm for a Niger Triggerfish. It is our own starting plan, not a vet's advice, and you can change every line in the app.

FeedingSmall amounts once or twice a dayevery day
Temperature checkevery day
Salinity checkevery week
Top-upTop up evaporation with fresh RO water, not salt waterevery day
Water testevery week
Water changeAbout 10 to 20% of the waterevery 2 weeks
Glass cleanevery week

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Where this comes from

Every breed page shows where each fact comes from. If we got something wrong, sorry, we are pet people, not a science magazine. Tell us at [email protected] and we will fix it.

FishBase: Odonus niger summary fishbase.seused for names, distribution, depth, length, diet, breeding behaviour, IUCN status
Wikipedia: Red-toothed triggerfish en.wikipedia.orgused for names, description, colour, swimming style, behaviour, taxonomy
LiveAquaria: Niger Triggerfish liveaquaria.comused for aquarium care level, tank size, water parameters, diet, temperament

Checked 2026-09-30. Text is written in our own words from these sources.