Black skirt tetra

Overview

The black skirt tetra (Gymnocorymbus ternetzi) is a tall, deep-bodied tetra with a smoky silver front fading to black, and long trailing anal fins that give it its “skirt”. Bigger and bolder than most small tetras, it’s also one of the toughest — undemanding, adaptable and forgiving of beginner mistakes. A shoal drifting through planting has real presence, and their hardiness makes them a genuine beginner fish.

Tank & water

A hardy, larger tetra that needs swimming room and a group:

• A cycled tank of at least 75 litres — cycle the aquarium before adding fish and check how many fish in an aquarium.
• Temperature 20–26 °C with a reliable heater; they tolerate slightly cooler rooms than most tetras.
• Soft to moderately hard water (pH 6.0–7.5) — very adaptable. Gentle to moderate filtration suits them.
• A planted layout with open water — plants for cover and clear space for the shoal to cruise.

Feeding

Black skirts are unfussy omnivores with good appetites. A staple tropical flake or pellet, plus frozen or live daphnia, brine shrimp and bloodworm, keeps them in good condition. Feed small amounts once or twice a day. See our fish food and best fish food guides.

Tankmates

Generally peaceful in a group, black skirts suit robust community tanks. Good companions include other sturdy tetras like serpae and lemon tetras, danios, barbs, corydoras and peaceful gouramis. Avoid slow, long-finned fish such as bettas, guppies and angelfish, whose fins may be nipped. Matched sensibly, they’re an easy, characterful shoal.

For a stable, planted community with room to swim, our best aquarium for beginners guide is a good start — black skirt tetras are one of the most beginner-proof shoals around.