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Black Phantom Tetra

Megalamphodus megalopterus

Also called Hyphessobrycon megalopterus (former name)

SpeciesShort profile

From South America: upper Rio Guaporé (Río Iténez) and upper Rio Paraguay basins in Bolivia and Brazil123

At a glance the quick version

Length3.6 to 4.4 cm123
Sizesmall
Very peaceful community fish
Striking contrast between black males and red-finned females
Lively shoaling and display behaviour
13

Looks how to spot one

Small, deep-bodied scaled characin

A compact, almost diamond-shaped tetra in smoky grey to near-black tones. Behind the gill cover sits a dark shoulder patch framed by a shimmering silver edge. Males carry large, fully black fins, while females show red on the pelvic, anal and adipose fins. Breeders have also produced a long-finned form.13

Colourssmoky grey to black bodyblack shoulder patch with silver rimblack fins (males)red-tinted lower fins (females)13

Personality what they are like

Gentle and easy-going with other fish. Males like to show off to each other by spreading their big black fins, which is all display and part of the charm of a well-sized group.13

Daily activity how busy a day looks

Active mid-water swimmer that benefits from open swimming space alongside planted areas.1

Grooming and care the hands-on bits

Hardy and adaptable once settled. Regular partial water changes and a varied diet keep the colours at their best.1

Home where they are happiest

Tank with a base of at least about 80 x 30 cm (around 72 litres), although FishBase gives 60 cm as a minimum length. Temperature roughly 20 to 28 °C, pH about 5.0 to 7.5, soft to moderately hard water (1 to 12 dGH). Plants, wood and subdued light suit it well.12

Food basics what goes in the bowl

Omnivore. In the wild it eats small invertebrates, worms and some algae. In the aquarium give good dried foods plus small live or frozen foods such as bloodworm, mosquito larvae, Daphnia and Moina.12

Company who they like around

Shoaling fish: keep at least 5 together, ideally 8 to 10 or more, with similar-sized peaceful tankmates.12

The story where it all began

Carl H. Eigenmann described the species scientifically in 1915 from material collected at Cáceres in Mato Grosso, Brazil. The black form reached European aquarists through German importers in the 1930s, and today nearly all fish in the hobby are bred in captivity. It was later moved from Hyphessobrycon to the genus Megalamphodus.31

Fun facts for the dinner table

  1. 1

    Wild populations differ by region: the black form comes from the Guaporé basin, while fish from the southern Pantanal around 700 km away are naturally reddish.3

  2. 2

    Males and females look so different that they can be told apart at a glance by fin colour: black for males, red-tinged for females.1

  3. 3

    In the wild it mixes with other small species in shoals and forages among plants near the shore.3

  4. 4

    A long-finned variety has been developed by captive breeders.3

Recognised by the official bits

IUCN Red List
Least Concern (assessed 4 March 2021)2
FishBase
Listed as a commercial aquarium species2

The care rhythm a typical week and year

A typical home-care rhythm for a Black Phantom Tetra. A starting point, not a vet's advice.

Owner questions the things everyone asks

How often should I feed my Black Phantom Tetra?

Feed your Black Phantom Tetra small amounts once or twice a day. Furry Diary's starting plan suggests this routine to keep them healthy and active.12 Pet Wiki plan

What does a Black Phantom Tetra eat, and what should it never eat?

As an omnivore, it enjoys good dried foods plus small live or frozen treats like bloodworm and Daphnia. For foods to avoid, it's best to ask a vet or experienced breeder, as specific restrictions vary.12

How much space does a Black Phantom Tetra need?

A tank with a base of at least 80 by 30 cm, around 72 litres, is recommended. They are active mid-water swimmers and appreciate open swimming space alongside planted areas.12

What temperature, light or water does a Black Phantom Tetra need?

Keep water temperature between 20 and 28°C, pH 5.0 to 7.5, and soft to moderately hard water. Subdued lighting with plants and wood suits them well.12

How often should I clean a Black Phantom Tetra's home?

Furry Diary's starting plan suggests a weekly 25% water change, weekly glass cleaning, and a monthly filter rinse using old tank water. Regular partial water changes keep their colours at their best. Pet Wiki plan

Can a Black Phantom Tetra live with others?

Yes, they are gentle and easy-going shoaling fish. Keep at least 5 together, ideally 8 to 10 or more, with similar-sized peaceful tankmates.12

How long does a Black Phantom Tetra live?

Lifespan varies with care and environment. For typical expectations, ask a vet or experienced breeder.

Can I handle a Black Phantom Tetra?

These delicate fish should not be handled. If you need to move them, use a net gently. Consult a vet for any health concerns.

Written from the sources on this page, a few checked guides (VCA, ASPCA, RSPCA) and Pet Wiki's own starting care plan. A friendly guide, not a vet's advice.

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Where this comes from

Every fact on this page has a numbered source. Spotted an error? [email protected].

  1. Seriously Fish: Megalamphodus megalopterus seriouslyfish.comused for range, size, care parameters, diet, behaviour, dimorphism
  2. FishBase: Megalamphodus megalopterus fishbase.seused for distribution, max length, water parameters, IUCN status, diet
  3. Wikipedia: Black phantom tetra en.wikipedia.orgused for history, colour forms, appearance, fun facts

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