Overview
- The Black Widow Tetra (Gymnocorymbus ternetzi), also sold as the black skirt tetra, is a hardy, deep-bodied tetra with black vertical bars and a dark rear half.
- Native to slow creeks and streams with overhanging plants in the Paraguay and Guaporé basins of Brazil, Bolivia and Argentina.
- Grows to about 2.4 in (6 cm) standard length.
- All fish in the trade are captive-bred, including long-finned and artificially colored forms. Avoid dyed fish.
Feeding
- Omnivorous and not fussy.
- Feed flakes and granules, with regular small live or frozen foods such as Daphnia and bloodworm.
Habitat
- A 30 × 12 in (75 × 30 cm) tank, such as a 20-gallon long (70 liters), suits a group.
- Open swimming space plus some dense planting and floating plants to dim the light.
- Water: 68–79°F (20–26°C), pH 6.0–7.0, GH 5–20.
Fish Care
- One of the best tetras for beginners and adapts to most setups.
Compatibility
- Good with most livebearers, danios, rasboras, other tetras, Corydoras and small plecos.
- Can live with robust dwarf cichlids such as kribensis.
- [UNVERIFIED] May nip long-finned fish such as bettas and angelfish, especially in small groups.
Aquarium Behavior
- Lively and generally peaceful.
- Keep a group of at least 6. Larger groups behave more naturally.
Breeding
- Quite easy, but use a separate tank to save fry.
- Use a dim tank around 18 × 12 × 12 in (45 × 30 × 30 cm) with java moss, spawning mops or mesh on the bottom.
- Eggs are adhesive and the parents will eat them, so remove adults after spawning.