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Maximum size : 12 cm

Bucktooth Tetra - Exodon paradoxus : Complete Fish Profile & Care Guide

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The Bucktooth Tetra (Exodon paradoxus) is a unique and unusual species that may not be suitable for a community aquarium. This Tetra is highly aggressive and will relentlessly attack most other tank mates, even those that are significantly larger and often considered aggressive themselves.

Due to their aggressive tendencies, it is highly recommended to house these fish in a species-only aquarium and in a large group to prevent individual targeting. While maintaining them in a larger group reduces the likelihood of any specific individual being targeted, it's important to note that occasional casualties may still occur. 

An ideal aquarium setup for the Bucktooth Tetra would feature a sand substrate supplemented with carefully arranged driftwood branches and roots for a naturalistic look. To create an optimal environment, heavily planting the tank with a variety of aquatic plants is recommended. This adds aesthetic value and provides essential shelter for the fish in case they need to escape bullying or aggression from their tank mates. Effective filtration is crucial to maintain water quality and keep the tank environment healthy to sustain a larger group of Bucktooth Tetras.

The Bucktooth Tetra has an elongated, translucent, and silvery-tan body with two distinct black spots, one located just before the tail and the other below the dorsal fin. The lower half of the dorsal fin is a bright and vibrant red. It's worth noting that the Bucktooth Tetra does not possess any actual teeth despite its name.

Bucktooth Tetra Photos

Sexual Dimorphism

Sexing Buck Tooth Tetras can be challenging due to minimal physical differences between males and females. However, mature males can be identified by their sleeker appearance and elongated anal and dorsal fin rays, which are slightly more pronounced than those of females.

Quick Facts

Scientific NameExodon paradoxus
Year Described1844
Other NamesExodon Tetra
OriginsBrazil Guyana Colombia
Max Size12 cm
Aquarium LevelMiddle - Top
DifficultyIntermediate - Advanced
Best kept asGroups 8+
LifespanUp to 10 Years

Water Parameters

Water TypeFreshwater
PH5.5 - 7.5
GH5 - 20
72 - 82
22 - 27

The Bucktooth Tetra has been featured on the following stamps.

Natural habitat

The Bucktooth Tetra is a captivating fish native to the Rio Branco, Guyana, Columbia, and South America's Amazon and Tocantins River Basins. These Tetras can be found in floodplain lagoons and rivers flowing through grasslands, where they gather at the water's surface. Sandy substrates are typical of their biotopes, and the presence of aquatic plants is scarce. It is fascinating to observe how the Bucktooth Tetras thrive in flowing waters and how they adapt to their environment. Their natural habitat serves as an inspiration for creating unique and beautiful aquarium setups.

How to breed the Bucktooth Tetra

Breeding Bucktooth Tetras can be a challenging task. To maximize your success, it is best to set up a separate breeding tank that provides a dimly lit environment, such as a tank with java moss or spawning mops that serve as ideal locations for the fish to lay their eggs. Alternatively, you can place some mesh or marbles at the bottom of the tank to allow the eggs to fall through while preventing the parents from reaching them.

You should add groups of at least half a dozen Tetras to the aquarium and condition them on a high-quality diet of live and frozen foods before and during spawning. You can also spawn them in pairs for a greater yield of fry. These pairs should consist of healthy females and males with the best colours, gravid and in their prime. To mimic natural breeding conditions, raising the tank's temperature slightly and adding slightly acidic water is recommended.

Inducing spawning can sometimes be done by raising the temperature of the water or performing a 50% water change. Once the eggs have hatched and the fry is free-swimming, removing all adults from the breeding aquarium as soon as possible is important since they may eat the eggs and fry.

Diet & feeding

A balanced diet is essential for the Bucktooth Tetra, and it is recommended to provide them with predominantly meaty foods, such as chopped prawns, bloodworms, earthworms, and mussels. Some individuals may also accept high-quality dried foods such as flakes, pellets, and granules. Providing your Bucktooth Tetra with a varied diet will ensure optimal health and vibrancy of their colouration.

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