AquaSage
Species library

Black Skirt Tetra

Gymnocorymbus ternetzi

Characidae

FishDifficulty: ●●○○○Data: well-established

About

The black skirt tetra is a hardy, deep-bodied characin from the Paraguay and Guaporé river basins of central South America, named for the smoky black rear half and flowing anal fin that fade to translucent grey with age. Lively and undemanding, it is an excellent community fish but carries a reputation as a fin-nipper, particularly when kept in cramped quarters or thin groups. A generous shoal in a spacious, planted tank with open swimming room keeps its energy focused inward and greatly reduces nipping.

Care

Keep in an active shoal of 8 or more (larger is better for curbing nipping) in a planted tank of at least 75 L with plenty of open swimming space. Occasional fin-nipper: avoid slow, long-finned tankmates such as bettas, angelfish and fancy guppies.

Diet

Adaptable omnivore; feed varied dry foods alongside regular frozen or live daphnia, bloodworm and mosquito larvae to maintain condition and activity.

Tankmate compatibility

Gets along with (4)

Possible with care (83)

Avoid (22)

Computed by the AquaSage engine for a spacious reference tank — always check the full verdict for your exact setup in the calculator.

Sources