Bucktooth tetra Care Guide: Diet, Tank Mates, Diseases, Breeding & More

Updated: December 17, 2022

The bucktooth tetra (or “BTT” for short) is a freshwater fish that is native to South America.

They’re a very peaceful community fish that does well in groups, and they’re a great addition to any aquarium.

Bucktooth tetras are very easy to care for, and they’re a great fish for beginners. In this guide, we’ll teach you everything you need to know about bucktooth tetra care.

You’ll learn about their diet, tank mates, lifespan, and more!

Species overview

The Bucktooth Tetra (Scientific name: Exodon paradoxus) is a freshwater fish that’s native to the Orinoco River Basin in South America.

They are a relatively small fish, only reaching about 2.5 inches (6.4 cm) in length at most. Even though they’re small, they are still a very popular fish because of their unique appearance.

As their name suggests, the Bucktooth Tetra has a set of large teeth that protrude from their mouths. These teeth give them a very distinct look that’s hard to forget.

In the wild, these fish are found in slow-moving waters with a lot of vegetation. This is something you’ll want to replicate in their tank if you want them to be comfortable and thrive.

Bucktooth Tetras are a very peaceful fish and do well in community tanks. They are compatible with a wide variety of other fish as long as they are of a similar size.


Bucktooth tetra

The Bucktooth Tetra is a very small freshwater fish that is known for its long, slender body shape. As the name suggests, these fish have large teeth that protrude from their mouths.

The teeth on a Bucktooth Tetra are actually quite small, but they’re very prominent because of how thin the fish’s lips are. This gives them a very toothy grin that can be a bit off-putting to some aquarists.

The body of the Bucktooth Tetra is a silver color with a slight blue hue. There is a black stripe that runs along the length of their body from the base of their tail to their snout. This stripe is bordered by a thin line of white.

The fins on a Bucktooth Tetra are all fairly small, but the dorsal and anal fins are the longest. Both of these fins have a black stripe running down the center with a white border on either side.

The Bucktooth Tetra is a very peaceful fish that does well in community tanks. They are not aggressive and will not bother other fish.


Bucktooth tetras have a lifespan of around 5 years. This is pretty typical for small freshwater fish.

As with all fish, there are a number of factors that can impact their lifespan. Things like water quality, diet, and stress can all shorten their life expectancy.

If you take good care of them and provide them with a good environment, they should be able to live a happy and healthy life for several years.


The Bucktooth Tetra can grow to be 2.5 inches long, but is usually closer to 2 inches. These are relatively small fish, which is good news for those of you with smaller tanks. They can be kept in tanks as small as 10 gallons, but 20 gallons is ideal.


Tank Size

The recommended minimum tank size for a school of six bucktooth tetras is 30 gallons. If you want to keep a smaller school you can get away with a 20-gallon tank but we wouldn’t recommend it.

Bucktooth tetras are active fish and will often swim in mid-level to top-level areas of the tank. They also prefer to be in groups so we recommend keeping at least six fish together.

Water Parameters

The Bucktooth Tetra is a freshwater fish that is native to the rivers of South America. In the wild, they inhabit slow-moving waters with lots of vegetation.

To recreate their natural habitat in your aquarium, you will need to maintain the following water parameters.

  • Water Temperature: 70-82 degrees Fahrenheit
  • pH Levels: 6.0-8.0
  • Water Hardness: 2-12 dGH
  • Alkalinity Levels: 4-8 dKH

What To Put In Their Tank

When it comes to setting up an aquarium for Bucktooth Tetras there are a few key things you need to keep in mind.

The first is that these fish come from fast-moving rivers in the wild. This means that they’re used to a lot of water movement.

You’ll need to replicate this in their tank by using a filter that can produce a decent amount of flow. We recommend something with a turnover rate of at least 10x the volume of your aquarium.

The second thing to consider is that Bucktooth Tetras are schooling fish. This means that they feel more comfortable and secure when they’re in groups.

We recommend keeping a school of at least 6-8 fish. If you’re keeping them in a larger tank you can get away with fewer fish, but we wouldn’t recommend going below 6.

When it comes to decor, these fish don’t have any specific requirements. A lot of aquarists like to include some plants and driftwood in their tanks, but it’s not necessary.

The important thing is to make sure that there’s plenty of open space for them to swim around in.

A sandy substrate is a good choice since it won’t damage their delicate fins.

Common Diseases

Bucktooth tetras are a fairly hardy fish, but that doesn’t mean they don’t get sick from time to time. The most common diseases that these fish experience are the usual freshwater culprits.

Ich is the most common, but various other infections and parasites can strike too. Be on the lookout for anything out of the ordinary so you can act fast.

White spots, scars, cuts, or a change in behavior are all causes for concern. Even a disease that isn’t very severe can progress into something serious if left untreated.

When you notice something it’s important to act fast. Consult your vet and begin treatment immediately. The sooner you act, the higher the chance is that your fish will recover.

Of course, the best way to keep the risk of disease low is by simply keeping the tank in great shape. Not providing clean, high-quality water conditions will significantly increase the chance of your Bucktooth tetra getting sick.

Behavior & Temperament

Bucktooth tetras are one of the more active fish on our list. They’re constantly swimming around and exploring their environment. Even when they’re not actively looking for food, they’re still on the move.

The only time you’ll see them slow down is when they’re resting. They’ll find a spot near the bottom of the tank and remain there until they’re ready to start swimming around again.

When it comes to temperament, bucktooth tetras are relatively peaceful. They’re not known for being aggressive and will usually leave other fish alone. The only time you might see aggression is if they’re competing for food.

Even then, the aggression is usually only displayed towards fish that are the same size or smaller. These fish have been known to nip at the fins of larger fish, but they rarely do any serious damage.

Tank Mates

When it comes to bucktooth tetra tank mates, you have a lot of options. These fish are peaceful and can get along with most community tank residents.

One thing to keep in mind is that bucktooth tetras are schooling fish. They like to be in groups of at least six and prefer to stick with their own kind.

With that in mind, here are some compatible tank mates that work well:


The breeding process for bucktooth tetras is a bit more difficult than other species. They’re not the easiest fish to sex and they’re very finicky when it comes to their environment.

The first step is to sex your fish. Females are typically larger than males and have rounder bellies. Males also have longer fins.

Once you’ve sexed your fish, you’ll need to set up a breeding tank. It should be at least 20 gallons and have a sponge filter. The water should be soft with a pH around 6.5.

You’ll also need to add some live plants to the tank. Bucktooth tetras like to lay their eggs on plants. Java moss is a good option.

When everything is ready, add two females for every male. Then, begin feeding them live foods. Bloodworms and brine shrimp are good options.

The breeding process will begin when the females start to lay their eggs on the plants. The males will then fertilize them.

Once the eggs are fertilized, the parents will eat them. So, it’s important to remove the parents as soon as the eggs are laid.

You can then move the eggs to a separate hatching tank. Keep the water temperature around 82 degrees Fahrenheit. The eggs should hatch in about 24 hours.

Once they hatch, you can start feeding the fry live foods. Baby brine shrimp are a good option.


All in all, the Bucktooth Tetra is an excellent fish for both beginner and experienced hobbyists alike. They’re relatively easy to care for, are relatively disease-resistant, and make a beautiful addition to any freshwater community tank.

We hope you’ve enjoyed this guide and that you feel confident enough to go out and get your own school of these little guys. They’re sure to bring you hours of enjoyment!