Furry Diary

Not furry, but we like them anyway.

Congo Tetra

Phenacogrammus interruptus

Also called African tetra

SpeciesShort profile

From Central Africa: the lower and middle Congo River basin in the Democratic Republic of the Congo and the Republic of the Congo. Most fish in the shops today are captive-bred in Asia and Eastern Europe.123

At a glance the quick version

Length6 to 8 cm123
Sizemedium
Rainbow shimmer across large reflective scales
Males grow elegant, flowing fins
Peaceful, active schooling fish for a roomy community tank
32

Looks how to spot one

Large-scaled African characin with long, flowing fins in males

A deep-bodied tetra with big, mirror-like scales that catch the light in bands of blue, red and gold. Grown males are bigger than females and carry a tall dorsal fin and a feathery, extended centre to the tail, while females stay shorter-finned and plainer. Young fish look fairly grey and only colour up as they mature.231

Coloursiridescent bluered to orange midbodyyellow-goldgreyish-violet tail with white edging3

Personality what they are like

A calm, sociable fish that is happiest in a group of its own kind. It swims actively in open water and gets along with most peaceful tankmates, though its bustle can unsettle very shy species. Without enough companions it tends to become timid.21

Daily activity how busy a day looks

An active midwater swimmer that needs plenty of open swimming length in the aquarium.21

Grooming and care the hands-on bits

Keep water clean and stable with regular partial water changes; good conditions help males develop their full fin length and colour.2

Home where they are happiest

A tank of at least 120 x 30 cm footprint (about 108 litres) for adults, with open swimming space plus planted areas. Water 23-28 C, pH about 6.0-7.5 (FishBase gives 6.0-8.0) and hardness around 3-19 dGH.21

Food basics what goes in the bowl

Omnivore. In the wild it eats small worms, insects, crustaceans and plant matter. In the aquarium offer a quality dry food plus regular live or frozen foods for best colour.21

Company who they like around

Keep in a mixed-sex group of at least 5-6. Good tankmates include other peaceful tetras, rainbowfish, Corydoras and calm cichlids; avoid fin-nipping or rough species.21

The story where it all began

The Congo tetra was scientifically described by George Albert Boulenger in 1899 from fish collected in the Congo basin. Its large size for a tetra and showy males made it a long-standing favourite in community aquariums, and today most stock is bred on fish farms.132

Fun facts for the dinner table

  1. 1

    Despite the name, it belongs to the African tetra family (Alestidae), not the South American tetras most people know.3

  2. 2

    A female can scatter up to around 300 eggs after an energetic chase by the male, and they hatch in roughly six days.1

  3. 3

    Young Congo tetras look quite plain grey; the rainbow colours and long fins appear only as they mature.2

  4. 4

    Fish reach maturity at about 9-12 months old.3

Recognised by the official bits

IUCN Red List
Assessed as Least Concern (February 2009)1
FishBase
Listed as commercially important in the aquarium trade1

The care rhythm Furry Diary remembers it for you

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

Start a free diary

You might also like

our little thank-you jar

Like what we are building? Buy us a coffee.

The breed atlas is free for everyone, with a source on every fact, and it will never show ads. If it helped you, a small tip keeps the research going. Any amount is lovely, and no is a perfectly fine answer too.

Leave a tip

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.

  1. Phenacogrammus interruptus, FishBase fishbase.seused for distribution, max length, water parameters, IUCN status, spawning, author
  2. Phenacogrammus interruptus, Seriously Fish seriouslyfish.comused for origin, size, tank and water parameters, diet, behaviour, appearance
  3. Congo tetra, Wikipedia en.wikipedia.orgused for colours, history, family, maturity, sizes

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