buenos aires tetra

Caring for Buenos Aires Tetra: The Ultimate Guide

Are you looking to add some color and life to your freshwater aquarium? If so, the Buenos Aires Tetra (Hyphessobrycon anisitsi) may be the perfect choice for you! This species is known for its active and outgoing nature, making it a great choice for those looking to create a lively tank.

However, keeping these fish at their peak health requires the proper environment and care. This guide will cover everything you need to know about caring for your Buenos Aires Tetras and giving them the best shot at a long, healthy life.

buenos aires tetra
Buenos Aires Tetra, silver-colored with a pink or reddish tint, a black band that runs along their midline, just above the dorsal fin.

Species Summary

The Buenos Aires Tetra has been a popular choice in the aquarium trade for over six decades and it’s easy to see why. These fish are easy to take care of, they bring plenty of life to your tank, and they are quite pretty to look at.

These freshwater fish are slender in shape and predominantly silver in color. A thin blue stripe runs from behind the gill plate down to the caudal fin, producing a beautiful shimmer in the right light. You’ll find a distinct diamond-shaped black mark at the base of their tail fin that can stretch up to meet the blue midline. The caudal, pectoral, and anal fins have a reddish-orange hue, while the dorsal fins are usually transparent. However, males have more vivid coloration than females, and females tend to be bigger and have a broader shape.

When fully grown, these tetras can reach up to 2.8 inches in length and live for three to five years under optimal conditions.

Buenos Aries Tetra Care

Since these fish are relatively low-maintenance and fairly forgiving in terms of environmental requirements, many aquarists mistakenly don’t give them the care they deserve. This mistake could cost you the quality of your fish’s life and even their lives altogether.

To help you prevent any potential setbacks, here’s what you need to know about Buenos Aires Tetra care:

Tank Size

The appropriate tank size for these fish will depend on how many you intend to keep in your aquarium. While some aquarists have succeeded in keeping a small group in 10-gallon tanks, we recommend providing at least 30 gallons for your Buenos Aires Tetras.

These are active schooling fish who need plenty of room to swim around and explore. Keeping them in a cramped tank can cause them stress and other health issues, so the bigger the better! If you’re going to keep multiple species in the same tank, make sure to factor in their tank size needs as well.

Water Parameters

The best way to keep your Buenos Aires Tetras healthy is to replicate the warm and soft water conditions of their natural habitat in Argentina. You should aim for a water temperature between 64°F and 82°F (aim for the middle of this range), a pH range between 5.5 and 8.5 (with neutral pH being the ideal), and a water hardness of 12 to 35 dGH.

It’s also important to check the conditions of your tank weekly once it’s established so that any subtle changes in water parameters won’t take you by surprise.

What To Put In Their Tank

Buenos Aires Tetras won’t be too picky about the type of decorations in their tank, but there are a couple of things that you should include to make them feel more comfortable. Adding plants is always a good idea for these fish, as it gives them plenty of places to hide and explore. Make sure to avoid sharp-leafed plants that could hurt their delicate fins.

You should also provide plenty of driftwood and rocks for them to swim around. Additionally, incorporating dim lighting and a dark substrate in the tank can bring out their magnificent colors even more.

Feeding and Diet

These fish are omnivores with a diet consisting of proteins and plant matter. To feed your Buenos Aires Tetras optimally, you should buy a portion of high-grade commercial fish food and feed them multiple times a day in small portions. Try to vary their diet and give them a mix of live and frozen foods to keep them healthy.

In addition to a quality staple diet, make sure to provide them with vegetables like blanched spinach or zucchini to ensure they get all their essential nutrients.

Tank Mates

When deciding which tank mates to put with Buenos Aires Tetras, it’s important to consider the species’ size and temperament. You should avoid keeping them with large or aggressive species and stick with those that are small enough to not view the tetras as food. Good tank mates include :

  • Danios
  • Barbs
  • Rasboras
  • White Cloud Mountain Minnows
  • and small Catfish like Corydoras

Aquarium Setup

When setting up your tank, it’s important to replicate the natural habitat of these fish as closely as possible. Buenos Aires Tetras require plenty of space to swim and explore, so a larger tank of at least 30 gallons is recommended. Be sure to provide plenty of structure in the form of rocks, driftwood, and plants, so that they have plenty of places to hide and play.

Additionally, a dark substrate and dim lighting will bring out the colors of the fish even more.

Disease Prevention

The best way to prevent illness in your Buenos Aires Tetras is to keep a close eye on their environment. Make sure to check on your tank’s water parameters weekly to ensure everything is as it should be. Additionally, you should quarantine any new fish before adding them to the tank to make sure they’re healthy. Finally, it’s important to stick to a consistent feeding schedule and provide quality food rich in proteins and vitamins.

Water Changes

If you want to provide your Buenos Aires Tetras with the best possible environment, it’s essential to perform regular water changes. Depending on the size of your tank and stock level, you’ll generally want to do a water change every two weeks. During water changes, you should also be sure to clean your filter media and any decoration, so that your fish won’t be subjected to any toxic build-up.

Adding Fish

When adding Buenos Aires Tetras to an established tank, it’s important to take your time and let them acclimate. Start by floating the bag they came in for 10-15 minutes so that the temperature in the bag matches the water in the tank. Then, start adding cups of water to the bag every couple of minutes until it’s full. After about an hour, you can net the fish out and add them to the tank.

Social Behaviour

Buenos Aires Tetras are very social creatures and should always be kept in groups of at least 8-10 individuals. In larger groups, they will display some impressive schooling behavior and will explore the tank together. Additionally, they are quite active and love chasing each other around the tank.

However, the males may become aggressive when competing for the attention of a female, so make sure to keep an eye on them.

Breeding Buenos Aires Tetras

If you’re looking to breed your Buenos Aires Tetras, you’ll need to create a conducive environment for the process. Start by setting up a separate breeding tank that’s about 20 gallons in size. Make sure to use dim lighting and incorporate plenty of plants and hiding spots for the female to lay her eggs in.

After that, you’ll need to condition the water to the right parameters and work on getting a pair. Once you’ve got a mating pair, you can add them to the tank and wait for them to spawn. Generally, the eggs will hatch in one to two days and you’ll be able to feed the fry infusoria until they’re big enough for more nutrient-rich foods.


Buenos Aires Tetras are a wonderful choice for beginners and experienced aquarists alike. These active and vibrant fish bring plenty of life to any aquarium and can be quite hardy if you provide them with the ideal environment.

To give your Buenos Aires Tetras the best chance at survival, make sure to set up an appropriately-sized tank and keep the water parameters within the recommended range. They should also be fed a balanced diet and provided with plenty of plants and hiding spaces. If you do all that, you can rest assured that your fish will be happy and healthy.