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

Updated: December 17, 2022

The Buenos Aires tetra is a freshwater fish that is native to South America. This species is known for its hardiness and is a popular choice for beginner aquarium enthusiasts.

Despite their popularity, there is still a lot of confusion surrounding their care. How big do they get? What do they eat? What are the best tank mates?

This guide will answer all of those questions and more. By the end, you’ll know everything you need to know about Buenos Aires tetra care.

Species overview

Buenos Aires tetras (Hyphessobrycon anisitsi) are a schooling fish that are found in dense groups in the wild. They are native to the Paraná River basin in South America, specifically in Brazil, Uruguay, and Argentina.

They prefer slow-moving waters with a lot of vegetation. This is something to keep in mind when setting up their aquarium as they will need a lot of plants to feel comfortable.

In the wild, these fish eat a diet of small insects, crustaceans, and worms. This is something that should be replicated in the aquarium with a high-quality fish food.

Buenos Aires tetras are a very popular fish in the aquarium scene due to their bright coloration and peaceful nature. They are a great choice for beginner fish keepers and make a great addition to most community tanks.


Buenos Aires tetra

The Buenos Aires tetra is a freshwater fish that’s very popular in the aquarium trade. They have a sleek and slender body that tapers off at the end.

They have a long dorsal fin that starts about halfway back on their body. This fin is taller than their anal fin, but both are relatively the same size.

The Buenos Aires tetra has a forked caudal fin that’s taller than it is wide. This fish also has small pectoral fins that are almost unnoticeable.

This species is silver in color with a few black stripes running down their sides. The stripes start at their gill covers and run all the way to the end of their tail.

The fins on this fish are clear with a hint of red. The red is most prominent on the tips of their dorsal and caudal fins.


The average Buenos Aires tetra lifespan is around 5 to 8 years. There are a number of things that can impact their life expectancy though.

As with any other fish, the level of care they receive is very important. If they’re in a well-maintained tank with good water quality then they’ll obviously live longer than if they’re in a subpar environment.

Their diet is also a factor. If they’re not getting enough nutrients then they won’t live as long as they otherwise could.


The average Buenos Aires tetra size is between 3 and 4 inches long. Some specimens have been known to grow a bit larger, but this is quite rare. They are a relatively small fish, which is good news for those who don’t have a lot of space in their tank.


Tank Size

The minimum tank size for Buenos Aires tetras is 20 gallons. This is assuming you want to keep a small school of 5 or 6 fish.

We recommend going with a larger tank if you can. Even a 30 or 40-gallon tank will give you a lot more flexibility when it comes to stocking your tank.

Water Parameters

The Buenos Aires tetra is one of those “easy to keep” fish that still requires some basic understanding of their needs.

For starters, they come from the Paraná River basin in South America. This is a huge river system with a variety of different environments.

The Buenos Aires tetra is typically found in slower-moving water with plenty of vegetation. That said, they are adaptable fish and can do well in a variety of different aquarium setups.

Here are a few water parameters to keep in mind when setting up a Buenos Aires tetra aquarium.

  • Water temperature: 72 to 82 degrees Fahrenheit
  • pH levels: 6.5 to 7.5
  • Water hardness: 2 to 12 dGH
  • Alkalinity Levels: 4-8 dKH

What To Put In Their Tank

When it comes to setting up an aquarium for Buenos Aires tetras there are a few things you need to take into consideration.

The first is that these fish come from fast-moving waters. This means that you need to have a strong filter that can provide them with adequate filtration and flow.

The second thing to think about is the substrate. These fish like to dig and root around, so you need something that won’t hurt them if they do that. A soft, sandy substrate is ideal.

As for plants, they can be a little hit and miss with these fish. They might nibble on them or uproot them, so it’s really up to you whether you want to include them or not.

In terms of décor, we recommend some driftwood or rocks. These will provide them with plenty of places to hide and feel secure. If you want to include plants, then choose something that can withstand a little abuse (hornwort or water wisteria are both good choices).

Common Diseases

Buenos Aires tetras are a hardy and durable fish, but they’re not immune to disease. The most common illness that affects this species is ich.

Ich is a very common freshwater fish disease that’s caused by a parasite. The most obvious symptom is the presence of white spots on the body of your fish.

If left untreated, ich can be fatal. However, it’s relatively easy to treat if you catch it early. There are plenty of ich treatment options available, so be sure to consult your vet if you think your Buenos Aires tetra has this disease.

Another thing to look out for is infection from cuts. The most common cause of this is keeping your fish in a tank with a rough substrate (or aggressive species that want to fight).

In general, the best way to prevent these fish from getting sick is to maintain the quality of the water in their tank. A tank with clean and stable water conditions always leads to healthier fish who are more resistant to disease.

Behavior & Temperament

The Buenos Aires tetra is a schooling fish, which means it does best when it’s around others of its own kind. In the wild, these fish school in groups of hundreds. So, if you’re keeping them in captivity, you should try to have at least six in your tank.

These fish are relatively peaceful. They’re not aggressive and get along well with other fish that have similar temperaments. The only time they may become aggressive is if they feel threatened or if they’re not getting enough food.

Buenos Aires tetras are active fish. They’re constantly swimming and exploring their environment. They’re also known to be jumpers, so it’s important to have a tight-fitting lid on your aquarium.

Tank Mates

The Buenos Aires tetra is a schooling fish, which means they do best in groups. In the wild, these fish school in groups of 100 or more. In the home aquarium, a group of six is a good starting point.

These fish are relatively peaceful, so they make good community tank mates. They can get along with other tetras, danios, barbs, and gouramis.

It’s best to avoid tank mates that are too small. Buenos Aires tetras are opportunistic feeders and might see smaller fish as food.

Some compatible Buenos Aires tetra tank mates include:


Buenos Aires tetras are one of the easier species of fish to breed. They don’t have too many specific requirements and will typically spawn in a community tank.

The first step is to set up a breeding tank. It should hold at least 20 gallons of water and have a lot of hiding places. This species likes to feel safe, so the more places to hide the better.

You’ll also need to add a few plants. Buenos Aires tetras like to lay their eggs on plants. Java moss is a good option.

Once the tank is set up, you can add the fish. Start with two males for every female. The males have longer fins and are a bit more colorful.

The next step is to trigger spawning. You can do this by raising the water temperature a few degrees or by doing partial water changes.

Once the eggs are laid, the male will guard them. He’ll fan them with his fins to keep them oxygenated.

The eggs will hatch in about 24 hours. When they do, remove the adults from the tank. They’ll eat the fry if given the chance.

The fry will feed on microscopic organisms in the water. You can supplement their diet with baby brine shrimp or other small live foods.


The Buenos Aires Tetra is an excellent fish for beginners and experienced fish keepers alike. They’re easy to care for, can live in a wide range of water conditions, and are relatively disease resistant.

They’re also a beautiful fish that will add some color and excitement to your tank.

Overall, we think the Buenos Aires Tetra is a great choice for anyone looking for a new fish, and we’re confident you’ll feel the same way once you get to know them!