The Bucktooth Tetra (Exodon paradoxus) is a highly aggressive, carnivorous freshwater fish native to the rivers and streams of the Amazon Basin. At 3cm, this juvenile already exhibits the species' classic shimmering silver body covered in sparkling scales and its distinctive double black shoulder spots. While beautiful and fascinating to watch, the Bucktooth Tetra is not your average community fish—it’s a true predator with specialized feeding behavior and is best kept in large, species-only aquariums.

This fish is perfect for experienced aquarists looking for a lively, coordinated shoaling predator with unique behavior and striking appearance.

🐠 Key Features:

• Scientific Name: Exodon paradoxus

• Common Name: Bucktooth Tetra

• Size: ~3cm (juvenile; adults reach 10–12cm)

• Lifespan: 5–10 years

• Temperament: Aggressive, predatory

• Difficulty Level: Advanced

• Origin: Amazon Basin (South America)

• Best kept in large groups of 10 or more to distribute aggression

🌊 Water Conditions

Bucktooth Tetras require clean, warm water and ample space due to their fast-swimming nature and territorial behavior.

• Temperature: 24–28°C (75–82°F)

• pH: 6.0–7.5

• Hardness: 5–12 dGH

• Tank Size: Minimum 55 gallons for a proper group

• Water Type: Freshwater

• Filtration: Strong, efficient filtration required

• Lighting: Moderate to bright

Use rocks, driftwood, and sturdy plants to create territory boundaries, but leave open areas for schooling and fast movement.

🐟 Tank Mates

Important: Bucktooth Tetras are not community-safe. They are notorious fin-nippers and will attack or eat smaller or slower tank mates.

Best tank setup:

• Species-only tank with 10+ Bucktooth Tetras

• Keep in large schools to diffuse aggression within the group

• Do not house with peaceful or similarly sized fish

Avoid entirely:

• All peaceful fish

• Any fish smaller than or slower than them

• Invertebrates, which will be eaten

They can sometimes be kept with large, robust, and fast fish (e.g., big cichlids), but only under expert supervision.

🍽️ Feeding Habits

Bucktooth Tetras are opportunistic carnivores and prefer meaty foods.

Recommended diet:

• Live or frozen foods: bloodworms, brine shrimp, chopped fish

• Freeze-dried krill or shrimp

• High-protein pellets or carnivore-specific flakes

• Occasionally small feeder fish or insects (with caution)

Feed once or twice daily with protein-rich foods. Remove uneaten food quickly to maintain water quality.

🧼 Care and Maintenance

• Strong filtration is a must due to their protein-heavy diet

• Regular water changes (25–30% weekly)

• Use a tight-fitting lid—these fish are fast and may jump

• Watch for signs of internal fighting or stress, even within groups

• Provide enough space to reduce dominance aggression

Bucktooth Tetras are not for beginners, but they reward experienced aquarists with fascinating behavior and a bold presence.

⚠️ Important Note

Do not confuse their beautiful appearance with peaceful schooling tetras. Bucktooth Tetras require special care, plenty of space, and the right setup to thrive.

🌿 Why Choose the Bucktooth Tetra?

The Bucktooth Tetra is a bold, eye-catching species that commands attention. With their coordinated attacks, shimmering silver bodies, and fearless feeding behavior, they make for a fascinating display in properly managed species-only tanks.