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Red Tail Hemiodus Tetra (Hemiodus Gracilis) Care Guide

It is a relative of the medium-sized tetra. The slender hemiodus is one of the most wanted fish by aquarists since it has such a stunning appearance. If you are a true aquarist, you’d agree that this fish indeed has its attraction.

Adding this fish will surely make your community tank more vibrant and fantastic.

Species Overview

Level of CareModerate
AppearanceTheir main color is greenish hues, having a black band that starts in the middle of the body and makes the finish at the lower edge of their fin. Some of them also have a red tail.
Life ExpectancyApproximately 8 years
Size15 cms
Tank Size55 gallons
Tank EnvironmentWarm, slightly acidic water and will do best when given plenty of cover in the form of driftwood or tall plants
Tank MatesOther peaceful fish


It comes from the wide areas of the Amazon and Orinoco basins. The researchers found them doing as mixed-species shoals and living alongside the other schooling tetras. The species is peaceful and friendly, as well as active.

They prefer to live in a tank that has similar characteristics to their natural origins. Therefore, the aquarists will need to prepare a little acid water, and plenty of cover from the tall plants, driftwood, and some floating plants as well.

Delicate Fish

It is imperative to keep in mind that your slender hemiodus buddies are delicate fish. There is no way to put this fish as a single addition to your community tank. The owners must keep them in a school with their fellow friends.

Because of the natural habitats, it is safe to give ample size for the schooling fish. You will never add delicate fish to the nano aquarium.

They are peaceful species that will strive in groups. It is also easy to care for and maintain the fish as a beginner. If you have just started your aquarium hobby, you won’t find it difficult to treat and pet this fish.

With the right tank size and a great environment, they will appreciate your efforts and strive for a longer time.

Behavior & Characteristics

The hemiodus tetras are skittish and peaceful. Perhaps it is the characteristic that amazes aquarists the most. Every time you arrive home after a hectic day, you will smile a lot when you see your tetras welcoming you.

In their natural habitat, they are easily found in highly oxygenated water and streams with plenty of vegetation. Well, it is sensible since they have such a great metabolism system that demands plenty of oxygen intake daily. They move fast and are active most of the time. Their natural behavior will make your day!

The red-tailed hemiodus has a wiry body that is slightly flattened. Their main color is greenish hues, having a black band that starts in the middle of the body and finishes at the lower edge of their fins. They have a bold red flap below the band.


Cared for at the maximum quality, they can reach up to 15 cm or more in length.


They might not be the main items in the tropical fish shops. But you can easily find the specimens through an online marketplace in your country. You will find a store or two that can cater to your needs.

The key here is to focus only on the top-rated sellers so that you can get the best value for your money.

Tank Setup

The success key to setting up the best tank for your hemiodus is by referring to the natural habitat of your cute buddy.

As mentioned, they usually live in highly oxygenated water with streams and plenty of plants. Therefore, you will have the best ideas for decorating your aquarium and setting up your tank to be the closest to its natural habitat.

Tank Size

Your red-tailed tetras will thrive in the densely planted aquarium. Consider preparing at least 55 gallons for your schooling tetras and their other tank mates.


The larger and longer aquarium could be the best dimension for their dwelling. The home of your fish must be accompanied by a sandy substrate.

You could also combine it with fine gravel. Not to mention that you could add some branches and roots around them. These will closely mimic the origin areas of your hemiodus.

Consider adding some strong root plants as well.

Sometimes, the light in the tank can be too bright for your tetras. They also need the feel of afternoon and dawn. You could mimic it by adding some floating plants. This will give enough shade and prevent them from being anxious.

As mentioned, the fish can be skittish most of the time. With the help of floating plants like water lettuce, you can calm them down for a bit. It would be beneficial if you think that their behavior are too skittish.


A good quality filter is a must to keep the water clean and high in oxygen levels. The high oxygenated water will keep them motivated and healthy. Not to mention that it will improve their overall wellness and longevity.

Although they are not designed as jumpers, you will want to put a tight-fitting cover on your tank to prevent them from leaping and getting out of your tank.

Your hemiodus pets highly demand great water quality. They are sensitive to poor water conditions. Therefore, you will need to regularly change the water partially to keep it clean and safe for your schooling fish. Also, don’t make them flock to a smaller aquarium. They will be distressed to die.

Red tail hemiodus group

Maturing the Tank

Your first 5 days of preparation can be the most determining factor for your tank’s readiness. After purchasing a tank, you might feel excited that you want to add your new one with plenty of fish. But you need to let it settle for at least two days to set the temperature and make settings on the decorations, substrates, filtration system, and so on.

Do not add too many fish at once. Rather, you will want to start from a tiny group first to preserve the safe levels of ammonia and nitrite in your tank.

The water will turn cloudy because of the bacteria. Your new fish might be hiding at first. In the first five to a fortnight, it can be stressful for them because they are suddenly moved to a new environment, which is pretty normal for all kinds of fish.

Make sure you have set the covers and hiding places for them. Whenever your pet feels shy, they will just need to go to their hiding place. When they feel secure and safe, you can rest assured that they will live longer and thrive.

Feed once daily in the first cycle. You will notice that your live foods can be finished in only a few minutes.

Don’t overfeed your pet since it will make the water cloudy.

Consult with your local aquarist expert to assist you with checking the chemical filtration and water changes.

If you notice that the ammonia and nitrite levels get back to zero, you could start adding additional tank mates to your existing fish.

Red Tail Hemiodus Tetra Tank Mates

Your red tail tetras can be a great tank mate in a community aquarium environment. But you will need to consider their natural behavior.

As we mentioned before, they are pretty skittish. Their movement is somewhat surprising and unpredictable so that the other tank mates can mistake them for an attempt to hunt them.

While the larger species won’t get intimidated by their behavior, the slow and smaller moving species will.

That’s why it is a no-go to add your slower fish there since it will be burdensome for them.

Your hemiodus fish are fast swimmers, although they don’t intend to intimidate the other fish. They can also be quite shy.

If you plan to house your red tail tetra in a single species, don’t add the solo individual. They are best treated in groups of at least 10 specimens. They will have more morale when flocking together. But before adding them to your aquarium, make sure they have matured first.

In the community tank, your hemiodus will be the perfect companion for these tank mates:

  • Geophagus
  • Characins
  • Heros
  • Catfish
  • Tatanoperca
  • Rainbowfish
  • Bala Sharks
  • Angelfish
  • Loricariids
  • Discus

Do not house them with the smaller species since they will intimidate their fellow tank mates.

Red tail hemiodus in a tank

Food & Diet

The hemiodus fish are carnivores. So, you will want to stick to meaty foods as much as possible. Giving them live foods daily is necessary to keep them healthy and active.

They don’t mind getting the flakes or other commercially packaged foods. But they’d prefer live, frozen, or dried meaty foods, including brine shrimp, blackworms, and so on.

Breeding Guidelines

Unfortunately, there is no recommendation for breeding this fish in the aquarium environment. It is seldom to see references to successful breeding. It is best to leave it to the experts who can help you to breed these tetras for you.