Black Widow Tetra Tropical Fish Information

Gymnocorymbus ternetzi
Black Widow Tetra
Behaviour Peaceful but may nip long-finned fish
Typical size 4cm
Max size 6cm
Tank Area Middle, top
Min Tank Size 60cm
Min Number in Tank 5
Temp Min: 20℃ Max: 26℃
Feeding Flake, frozen, live foods
pH Range 5.5-8.5
Hardness vs,s,m,h,vh
Black Widow Tetra Gymnocorymbus ternetzi
  • Black Widow Tetra Gymnocorymbus ternetzi - thumbnail
  • Black Widow Tetra Gymnocorymbus ternetzi - thumbnail

Black Widow Tetra (Gymnocorymbus ternetzi)

Black Widow Tetra Tropical Fish Learn all about the Black Widow Tetra's feeding habits and food types, its behaviour, its origins, its natural habitats, is it male or female, breeding advice and information, suitable tank mates, its sizing and growth range, minimum tank size, water PH and more. Use our fish community creator tool to plan your tank set up and ensure that the Black Widow Tetra is the right fish for your aquarium.

The Black Widow Tetra is a peaceful shoaling fish, which is very hardy and suited to a wide range of water conditions. After around a year, the black colour begins to fade to a washed out grey appearance and the fish no longer shoals, preferring its own space. Although very peaceful, the Black Widow Tetra will nip at long finned fish such as Guppies or Siamese Fighting Fish. Keep in aquariums with some hiding spots amongst plants. A good aquarium fish.

Black Widow Tetra Facts

Family Characidae (Characins) | Synonyms Tetragonopterus ternetzi, Gymnocothymbus ternetzii | Other names Black tetra, butterfly tetra | Origin South America; Paraguay and Guapore River basins | Breeding Egg scatterer | Natural Water Conditions pH 6-8, very soft to medium | Sexing Males dorsal fin is pointed and narrow whilst the anal fin is broader.

Black Widow Tetra Help and Advice

If you have a question about keeping Black Widow Tetra's then please use our Black Widow Tetra help forum. Join 100's of other fish enthusiasts with 1000's of years experience between them caring for and keeping fish like these.

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Check tank mates for the Black Widow Tetra fish species

You are in the thinkfish community creator for the Black Widow Tetra fish species, you can learn all about how the tool works in assessing fish tank mate compatibility at the link provided or use the tool tips provided to guide you. Create a test fish community that includes the Black Widow Tetra species and any other types of fish or crustacean you'd like to introduce - You can assess the best companions, tank size suitability, stocking levels based on filter type and volume and possible negative interactions and warnings as you build up your aquarium.

Please do check your water type for compatibility with your fish, which can be found on the Black Widow Tetra information box above and your local water company providers website. Don't waste your money and endanger your fish!
Tank Details
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