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Black Skirt Tetra
Gymnocorymbus ternetzi

Deep-bodied tetras with striking black fins. Can be nippy with long-finned fish like bettas and guppies — keep in groups of 6+ to spread aggression within the school. Hardy and long-lived (5+ years).

📏 Size: 5 cm
🐠 Tank: 20 gal
🌡️ Temp: 22–28°C
Easy

Quick Stats

Adult Size5 cm
Minimum Tank20 gal
Temperature22–28°C
pH Range6.0–7.5
Hardness (GH)4–15 dGH
DifficultyEasy
TemperamentSemi-aggressive
DietOmnivore — flakes, micro pellets, frozen foods
Schooling6+ required

Tank Setup

The Black Skirt Tetra (Gymnocorymbus ternetzi) requires a minimum tank size of 20 gal. For a species this size, a larger tank is always better — more water volume means more stable parameters and a healthier environment.

Water parameters should be maintained within the following ranges: temperature 22–28°C, pH 6.0–7.5, and hardness 4–15 dGH. These are relatively tolerant fish that adapt to a range of conditions.

Provide appropriate hiding places, a suitable substrate, and planted areas to match the natural behaviour of this species.

Tank Mates

Black Skirt Tetra are semi-aggressive fish. Choose tankmates carefully — they may not be suitable for all community setups.

Compatible tank mates include: Corydoras, Swordtail, Bristlenose Pleco, Black Phantom Tetra, Larger Tetras. Always ensure all species share similar water parameter requirements before mixing.

Schooling requirements: 6+ required. Keeping them in adequate numbers is essential for their wellbeing.

Diet & Feeding

Black Skirt Tetra are Omnivore. Feed a varied diet to ensure optimal health and colouration.

Omnivore — flakes, micro pellets, frozen foods

Feed small amounts 1–2 times daily. Only provide what the fish can consume within 2–3 minutes to prevent overfeeding and water quality issues. Supplement with live or frozen foods for optimal health and colour.

Common Health Issues

Like all aquarium fish, Black Skirt Tetra can be susceptible to common diseases including ich (white spot disease), fin rot, and bacterial infections. This species is generally hardy and disease-resistant when kept in good conditions.

Prevention is always better than treatment. Maintain stable water parameters, avoid overfeeding, quarantine new fish before adding them to the main tank, and perform regular water changes. A regular maintenance routine will prevent most health issues.

If disease does occur, isolate affected fish in a quarantine tank and treat appropriately. Always research medication compatibility before use — some treatments are toxic to invertebrates and scaleless fish.

Breeding

Breeding Black Skirt Tetra is possible in the home aquarium.

Provide appropriate breeding conditions — caves or hiding places for egg-laying species. Condition breeding pairs with high-quality foods before attempting to spawn them.

Many Black Skirt Tetra will breed readily without intervention. Be prepared to remove eggs or fry if you want to raise them — adult fish may eat their own young.

Frequently Asked Questions

What size tank does a Black Skirt Tetra need?

A Black Skirt Tetra needs a minimum tank size of 20 gal. However, larger is always better — more water volume means more stable water parameters and healthier fish.

Are Black Skirt Tetra easy to keep?

Black Skirt Tetra are rated as Easy difficulty. Beginners can keep them successfully with proper research and a cycled tank.

What do Black Skirt Tetra eat?

Black Skirt Tetra are Omnivore. Feed a varied diet including flakes, micro pellets, frozen foods.

Can Black Skirt Tetra live with other fish?

Black Skirt Tetra are semi-aggressive. Compatible tankmates include: Corydoras, Swordtail, Bristlenose Pleco, Black Phantom Tetra, Larger Tetras. Always research compatibility before mixing species.