Black Tetra (Gymnocorymbus ternetzi)

The Black Tetra (Gymnocorymbus ternetzi) is a compact, peaceful freshwater fish that thrives in community tanks, making it a favorite for both beginners and seasoned aquarists. Its striking dark silhouette and lively schooling behavior bring dynamic movement to any setup.

• Scientific name: Gymnocorymbus ternetzi
• Common name: Black Tetra
• Size: Typically grows to about 2 inches (5 cm) in length
• Color & appearance: Deep black body with translucent fins and a subtle iridescent sheen under bright lighting
• Behavior: Peaceful, active, and highly social when kept in groups
• Tank requirements: Freshwater, adaptable to a range of setups; prefer 72–82°F (22–28°C), pH 6.5–7.5, soft to moderate water hardness
• Diet: Omnivore; accepts flake, pellets, frozen, and live foods
• Compatibility: Best in community tanks with small to medium-sized, non-nippy species

The Black Tetra shines when kept in a proper school, where a group of 6 or more will showcase coordinated swimming and energetic foraging. They are relatively sturdy, forgiving of minor water parameter fluctuations, and respond well to a varied diet, which helps maintain color and vitality. This makes them an excellent choice for beginners building a community tank, as well as experienced aquarists who want reliable, animated inhabitants.