Serpae Tetra Species Care, Tank Mates, & More

serpae tetra
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Last Updated: September 4, 2023 by Flora Gibbins

Are you on the hunt for a vibrant and playful fish to liven up your aquarium? Check out Serpae Tetras! These little swimmers are a favorite among fish enthusiasts for their dazzling appearance and active behavior. These small, vibrant fish are a popular choice among aquarists for their striking appearance and active personalities.

Their coloring is striking, with deep red bodies and black markings around the tail fin and dorsal fin. These black markings can vary in size and shape, but they always make the fish stand out in a crowd.

Let’s now look into this lively and colorful tetra species that can add a lot of personality to any aquarium.

Serpae Tetra Facts and Overview

  • Common Names: Serpae Tetra, Red Minor Tetra, Jewel Tetra
  • Scientific Name: Hyphessobrycon eques
  • Adult Size: Up to 1.5 inches in length
  • Lifespan: Up to 5 years
  • Colors and Markings: Vibrant red bodies with black markings around the dorsal and tail fins
  • Origin: South America, specifically the Paraguay River basin

Origin and Distribution

Serpae Tetras are native to South America, specifically the Paraguay River basin. In the wild, you’d find them in slow-moving streams and flooded areas. They are known to be hardy fish that can tolerate a range of water conditions, which is one reason why they have become a popular choice among aquarium hobbyists.

In their natural habitat, Serpae Tetras tend to congregate in schools near the bottom of the water column. They are omnivores and will feed on a variety of foods, including insects, small crustaceans, and plant matter.

They were first introduced to the hobby in the 1930s, and since then, they have become a staple in the aquarium trade due to their striking appearance and active behavior.

Behavior and Temperament

Serpaes are generally peaceful but can be a bit nippy towards other fish, especially those with long, flowing fins. As such, it’s best to avoid keeping them with slow-moving or delicate fish, such as Betta fish.

One of the most interesting things about Serpae Tetras is their schooling behavior. In the wild, they swim together in large groups near the bottom of the water column. This behavior helps protect them from predators and also allows them to search for food more effectively.

In an aquarium, Serpae Tetras should be kept in groups of at least six to eight individuals to ensure they feel comfortable and can exhibit their natural behavior. When kept in smaller groups, they may become stressed and aggressive toward other fish in the tank, despite their tiny size.

In addition to their schooling behavior, Serpae Tetras are also known for being very active and playful fish. They are constantly on the move, darting around the tank and exploring their surroundings.

Serpae Tetra Tank Mates

When it comes to choosing tank mates for Serpae Tetras, it’s important to keep their behavior and temperament in mind. As previously mentioned, Serpae Tetras can be quite nippy towards other fish, so it’s best to avoid placing them with delicate fish.

Compatible Fish Species

Good tank mates for Serpae Tetras include other active, mid-level swimmers that can hold their own in a community aquarium. Some examples of compatible fish species include:

  • Danios
  • Rasboras
  • Corydoras catfish
  • Gouramis
  • Rainbowfish

They can also coexist with certain other types of tetra fish, but some other tetras are known to be fin nippers, so it’s best to avoid keeping them with Serpae Tetras. Examples of tetras that may not be a good fit include Black Skirt Tetras and Buenos Aires Tetras.

On the other hand, there are some tetra species that can coexist peacefully with Serpae Tetras. Some examples include:

When introducing new fish to an aquarium, observe their interactions closely and ensure that everyone is getting along. If you notice any signs of aggression or stress, it may be necessary to separate certain fish to prevent further harm.

Non-Fish Tank Mates

Serpae Tetras can also coexist with non-fish tank mates, such as snails and shrimp. However, it’s important to keep in mind that some fish may view them as food, so keep an eye on them.

Tank Mates to Avoid

As previously mentioned, it’s best to avoid keeping Serpae Tetras with slow-moving or delicate fish, as they can be prone to nipping and aggression. Some fish species to avoid keeping with Serpae Tetras include:

serpae tetra

Serpae Tetra Care

Taking care of Serpae Tetras is crucial to ensuring they are happy and healthy in your aquarium. To make this happen, it’s important to provide them with a balanced diet, the right water conditions, and a comfortable habitat. In this section, we’ll dive into some essential Serpae Tetra care tips that can help you keep your fish thriving. Whether you’re a seasoned fish keeper or new to the hobby, these guidelines can help you provide the best possible care for your finned friends.

Tank Setup

When it comes to keeping Serpae Tetras in an aquarium, it’s important to replicate their natural environment as closely as possible. Setting up the right tank environment is critical to the health and well-being of your Serpae Tetras. Here are some key factors to consider when creating the perfect habitat for your fish:

Tank Size

Serpae Tetras are small fish, but they are active and require plenty of swimming space. A good rule of thumb is to provide at least 10 gallons of water per six to eight Serpae Tetras. This will give them enough room to swim around and explore their surroundings.

What to Put In Their Tank

Serpae Tetras are active swimmers and appreciate plenty of hiding spots and decor in their tank. Adding live or artificial plants, rocks, and caves can provide them with places to rest and explore. When selecting decor, make sure to choose items that won’t harm your fish or alter the water chemistry of the tank.


Filters are important for maintaining good water quality in your Serpae Tetra tank. A good filtration system can help remove waste and keep the water oxygenated. Make sure to choose a filter that is appropriately sized for your tank.


When it comes to substrate, Serpae Tetras prefer a soft, sandy bottom. This can help prevent injuries to their delicate fins and make them feel more comfortable. Avoid using rough or sharp substrates that can cause harm to your fish.

Water Parameters

Maintaining the right water conditions is crucial to the health and well-being of your Serpae Tetras. Here are some key water parameters to keep in mind when caring for your fish:


Serpae Tetras are tropical fish and require a water temperature between 72 and 80 degrees Fahrenheit. Keeping the water temperature within this range can help prevent stress and disease.

pH Level

Serpae Tetras prefer a slightly acidic to neutral pH level between 6.0 and 7.0. Do check the pH level regularly to ensure it stays within the appropriate range.

Water Hardness

Serpae Tetras prefer slightly soft to medium-hard water with a hardness level between 5 and 15 dGH. This can help prevent stress and keep your fish healthy.

Water Changes

Performing regular water changes is important for maintaining good water quality in your Serpae Tetra tank. Try to change 10 to 20 percent of the water in the tank every one to two weeks to keep the water clean and fresh. You might also want to try using a high-quality water conditioner when adding new water to the tank to remove harmful chlorine and chloramines. Avoid using untreated tap water, as this can contain toxins and chemicals that are harmful to your fish.

Diet and Feeding

What They Eat

Serpae Tetras are omnivores and will eat a variety of foods, including flakes, pellets, and live or frozen foods like brine shrimp and bloodworms. It’s important to provide a varied diet to ensure they receive all the necessary nutrients.

In addition to commercial fish food, you can supplement your Serpae Tetras’ diet with live or frozen foods like daphnia, mosquito larvae, and chopped earthworms. These foods are high in protein and can help keep your fish healthy and active.

Feeding Guidelines

When feeding your Serpae Tetras, it’s important to avoid overfeeding. Aim to feed them small amounts two to three times per day, rather than one large meal. This can help prevent digestive issues and keep the water in the tank clean.

Make sure to remove any uneaten food after a few minutes to prevent it from decomposing and causing water quality issues. Uneaten food can also contribute to poor water conditions and disease.


Adding supplements to your Serpae Tetras’ diet can help promote good health and vitality. Some supplements you may want to try include vitamin C, which can boost the immune system, and garlic, which can help keep parasites and other illnesses away.

Common Diseases

Like any living creature, Serpae Tetras are susceptible to a variety of diseases and health issues. Here are some common diseases to look out for and how to prevent and treat them:


Ich, or white spot disease, is a common parasite that can affect Serpae Tetras. Symptoms include white spots on the fins and body, clamped fins, loss of appetite, and lethargy.

To prevent ich, make sure to maintain good water quality and avoid overcrowding in the tank. Treatment typically involves medication and raising the water temperature to 86 degrees Fahrenheit for a period of time.

Fin Rot

Fin rot is a bacterial infection that can cause the fins to deteriorate and fray, and the culprits are usually poor water quality, injury, or stress. Symptoms include ragged fins, discoloration, and lethargy.

To prevent fin rot, make sure to maintain good water quality and avoid overcrowding in the tank. Treatment typically involves medication and improving water conditions.

Swim Bladder Disease

Swim bladder disease is a condition that affects the fish’s ability to control its buoyancy. It can be caused by overfeeding, constipation, or bacterial infection. Symptoms include swimming upside down or sideways, or difficulty swimming.

To prevent swim bladder disease, make sure to feed your fish a balanced diet and avoid overfeeding. Treatment typically involves adjusting the fish’s diet and adding medication to the water.


Dropsy is a bacterial infection that can cause the fish to become bloated and have raised scales. It can be caused by poor water quality, stress, or injury. Symptoms include swelling, lethargy, and loss of appetite.

To prevent dropsy, make sure to maintain good water quality and avoid overcrowding in the tank. Treatment typically involves medication and improving water conditions.

By monitoring your Serpae Tetras regularly and taking prompt action if you notice any signs of illness, you can help prevent and treat common diseases and ensure the long-term health of your fish.

Breeding Serpae Tetras

breeding Serpae Tetras can be a challenging but rewarding experience for aquarium hobbyists. By providing the right conditions and monitoring your fish closely, you can help encourage successful breeding and raise healthy, thriving fry.

Here are some tips and guidelines for success:

Gender Differences

Male and female Serpae Tetras can be distinguished by their physical appearance. Males are typically more brightly colored and have longer, more pointed fins, while females are duller in color and have shorter fins.

The Breeding Process

Here’s a walk-through of the steps for breeding Serpae Tetras

  1. Provide the right environment: Set up a breeding tank with plenty of hiding spots and decor to encourage breeding behavior. Make sure to maintain good water quality and a stable temperature to reduce stress and promote spawning.
  2. Separate the males and females: Place the male and female Serpae Tetras in separate tanks for a few days to encourage breeding behavior. This can help the males become more colorful and the females to develop eggs.
  3. Introduce the breeding pair: After a few days of separation, place the male and female Serpae Tetras in the breeding tank together. Watch for signs of courtship, such as chasing and displaying colorful fins.
  4. Observe spawning behavior: Once the male and female Serpae Tetras are displaying courtship behavior, watch for signs of spawning. The female will release her eggs, which the male will fertilize.
  5. Remove the parents: After spawning, remove the male and female Serpae Tetras from the breeding tank to prevent them from eating the eggs or fry.
  6. Care for the eggs and fry: The eggs will hatch within a few days, and the fry will need to be fed small, frequent meals of infusoria or commercially available fry food. Make sure to maintain good water quality and provide plenty of hiding spots and decor for the fry to grow and develop.

Breeding Tips

Here are some additional tips to help ensure successful breeding of Serpae Tetras:

  • Monitor water conditions: Serpae Tetras are sensitive to changes in water conditions, so it’s important to monitor the water quality regularly. Perform frequent water changes and use a high-quality filtration system to keep the water clean and healthy for your breeding fish.
  • To initiate breeding, you can try increasing the temperature of the water and adding a spawning mop or other breeding substrate to the tank. The male will typically initiate courtship by chasing the female around the tank and performing a mating dance.
  • Use a separate breeding tank: Using a separate breeding tank can help protect the eggs and fry from other fish in the tank. It also allows you to maintain optimal water conditions for breeding and caring for the fry.
  • Feed a varied and high-quality diet: Feeding your breeding fish a varied and high-quality diet can help promote good health and egg production. Try supplementing their diet with live or frozen foods like brine shrimp, daphnia, and bloodworms.
  • Watch for signs of stress: Serpae Tetras can become stressed during the breeding process, especially if they feel threatened or crowded. Watch for signs of stress, such as clamped fins or loss of appetite, and make adjustments to the tank environment as needed.
  • Be patient: Breeding Serpae Tetras can take time and patience. Don’t be discouraged if you don’t see spawning behavior right away. Providing the right environment and care can increase your chances of successful breeding over time.

FAQ’s on Serpae Tetras

Can I breed Serpae Tetras in a community tank?

It is possible to breed Serpae Tetras in a community tank, but it can be challenging. Other fish in the tank may eat the eggs or fry, or the breeding pair may become stressed by the presence of other fish. It’s generally recommended to use a separate breeding tank for the best results.

Do Serpae Tetras jump out of the tank?

Serpae Tetras are not known to be frequent jumpers, but they may jump out of the tank if they feel stressed or threatened. Make sure to keep the water level in the tank topped up and provide a tight-fitting lid to prevent escape.

Can I keep Serpae Tetras with live plants?

Serpae Tetras can coexist with live plants, but they may nibble on the leaves or uproot them if they are not provided with enough hiding spots and decor. Choose hardy plants like Java Fern and Anubias, and provide plenty of hiding spots to help protect the plants.

Related Species

Serpae Tetras are a member of the Characidae family and are closely related to other species of tetras. Here are some related species that you may be interested in:

  • Neon Tetras (Paracheirodon innesi): Neon Tetras are small, colorful fish that are popular in the aquarium trade. They have a bright blue stripe down their sides and a red stripe beneath it.
  • Black Skirt Tetras (Gymnocorymbus ternetzi): Black Skirt Tetras are larger than Serpae Tetras and have a black stripe down their sides. They are peaceful and can coexist with other peaceful fish in a community tank.
  • Bloodfin Tetras (Aphyocharax anisitsi): Bloodfin Tetras have a distinctive red color on the lower part of their body and fins. They are peaceful and can be kept with other peaceful fish in a community tank.
  • Rummy Nose Tetras (Hemigrammus rhodostomus): Rummy Nose Tetras have a red nose and a silver body. They are peaceful and can be kept with other peaceful fish in a community tank.
  • Cardinal Tetras (Paracheirodon axelrodi): Cardinal Tetras are similar in appearance to Neon Tetras, but have a larger red stripe and a deeper blue color. They are peaceful and can be kept with other peaceful fish in a community tank.

Are Serpae Tetras for Your Aquarium?

Serpae Tetras are a popular and colorful species of fish that can make a great addition to a community aquarium!

While they are relatively easy to care for, they do have specific care requirements that should be considered before adding them to your aquarium.

With good water quality, a varied diet, and the right tank mates, Serpae Tetras can provide years of enjoyment and entertainment for aquarium hobbyists of all levels. Their bright red and black coloration and active behavior make them a standout species in any aquarium, and their compatibility with other peaceful fish makes them a great choice for a community tank.

Cover photo credit: Aline Zaninella de Oliveira Cardoso, CC BY-SA 4.0, via Wikimedia Commons

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