The black skirt tetra (also called black widow tetra) is one of the most adaptable and undemanding schooling fish in the hobby. Its striking two-tone appearance — silver-white front half transitioning to a flowing black skirt of extended fins — makes it an attractive addition to community tanks. Hardy across a wide range of water conditions, it remains a reliable classic for aquarists of all levels.
Natural Habitat
Wild black skirt tetras inhabit slow-moving rivers and flooded areas of the Paraguay and Guaporé river systems in South America. They prefer densely vegetated margins with soft, slightly acidic water and adapt readily to a wide range of captive conditions.
Water Requirements
| Parameter | Ideal Range |
|---|---|
| Temperature | 70–80°F (21–27°C) |
| pH | 6.0–7.5 |
| Hardness (GH) | 4–18 dGH (very adaptable) |
| Ammonia / Nitrite | 0 ppm |
| Nitrate | <30 ppm |
Tank Setup
A 20-gallon long tank suits a school of 6–8. Active mid-water swimmers that appreciate open space with planted borders. Moderate flow and subdued to moderate lighting preferred. Dark substrate enhances contrasting coloration. Note: mild fin nippers in small groups — avoid bettas and fancy guppies.
Diet
Omnivores. Quality flakes or micro-pellets twice daily; supplement with frozen bloodworms, daphnia, and brine shrimp. Active surface and mid-water feeders.
Temperament
Generally peaceful in groups of 8+. Compatible with: larger tetras, corydoras, rasboras, and medium-sized community fish. Avoid long-finned or very slow-moving fish.
Content reviewed for Gymnocorymbus biology accuracy.