Easy carePeacefulSchool of 6+South America

Bucktooth Tetra

Exodon paradoxus

The Bucktooth Tetra (Exodon paradoxus) is a peaceful fish that's easy to keep. Give it a tank of at least 170 litres (45 US gallons), water held at 73-82°F, and a pH of 5.5-7.5. Always keep a group of at least 6 - they feel safest in numbers.

Care levelEasy

TemperamentPeaceful

Min tank size45 US gal

pH range5.5-7.5

Temperature73-82°F

Max size4.7 in (12.0 cm)

Captive lifespan5-10 years

SchoolingYes · 6+ recommended

Captive lifespan reflects typical experience in a home aquarium, not maximum recorded age; genetics, sourcing, and care vary.

Natural distribution

Mostly South America

South America

Regional colours match the stocking calculator's origin map.

Bucktooth Tetra Tank Setup

Give them a tank of at least 170 litres (45 US gallons). As open-water swimmers they care more about swimming length than height, so a longer tank is ideal. Keep the water at 73-82°F with a pH around 5.5-7.5, and avoid sudden swings. Always keep a group of at least 6 of their own kind - kept alone or in pairs they tend to turn shy, nippy, or wash out in colour. They reach about 12 cm as adults, so don't be misled by the small juveniles sold in stores.

What Do Bucktooth Tetras Eat?

They have small mouths, so stick to small foods: crushed flake, fine granules, and now and then a treat of frozen or live foods such as daphnia or baby brine shrimp. Anything too large simply gets ignored.

Bucktooth Tetra Tank Mates

Keep in groups of at least 6. The Bucktooth Tetra is peaceful, which is the first thing to weigh up when you choose tank mates. It's a shoaling fish, so settle a group of 6 or more of its own kind before adding anything else - a stressed, lonely fish is far more likely to nip or hide. Before you buy, run your full stocking list through our stocking calculator. It weighs temperament, adult size, and water needs together, which a single species page can't do on its own.

Are Bucktooth Tetras Good for Beginners?

Often recommended to beginners, but only after the tank is cycled and you can keep a proper school - not three fish in a new setup.

Bucktooth Tetra - frequently asked questions

What size tank do Bucktooth Tetras need?

Bucktooth Tetras need a tank of at least 170 litres (45 US gallons). A bigger tank is always easier to keep stable, and gives them more room to settle in and behave naturally.

How many Bucktooth Tetras should I keep together?

Keep a group of at least 6. Bucktooth Tetras are a shoaling species and become stressed, lose their colour, or hide when kept singly or in pairs.

What water parameters do Bucktooth Tetras need?

Keep them at 73-82°F with a pH of 5.5-7.5, steady rather than chased to an exact figure. In a cycled tank, ammonia and nitrite should both read 0 ppm, with nitrate kept low through regular water changes.

What do Bucktooth Tetras eat?

Bucktooth Tetras have small mouths, so they need small foods. Crushed flake and fine granules form the staple, with the occasional treat of frozen or live foods such as daphnia or baby brine shrimp. Feed small amounts once or twice a day, and remove anything they don't eat.

Are Bucktooth Tetras good for beginners?

Yes - Bucktooth Tetras are a good beginner choice once the tank is fully cycled and you can keep a proper group. They are hardy but still need stable water and a school to feel secure.

Common mistakes with Bucktooth Tetras

Buying fewer than 6 - Bucktooth Tetras need a proper school to feel secure; isolated individuals hide, fail to colour up, or become stressed.
Underestimating tank size - the minimum footprint is 170 litres (45 US gallons); impulse buying into a smaller tank leads to stress and shortened lifespan.

Building a community? Run the full list through the stocking calculator before you add anything else.