Pristella Tetra (X-Ray Tetra): Care, Diet, Tank Mates & More!

Have you ever heard of the Pristella Tetra, also known as the X-Ray Tetra? These fish are stunning with their translucent bodies and shimmering silver scales, making them stand out in aquariums.

But aside from their mesmerizing appearance, they also make great tank mates and are relatively easy to care for.

Read on to discover everything you need to know about caring for Pristella Tetras, including their diet, tank mates, and more!

Species Summary

The Pristella tetra, also known as Pristella maxillaris, is found in the coastal rivers of South America. Despite its delicate appearance, this tropical fish has a resilient nature allows it to survive in various conditions.

It is known to migrate and relocate frequently due to environmental changes and flooding, making it well-suited for captivity.

The pristella tetra belongs to the characidae family and is notable for being the sole representative of the pristella genus.

These fish are native to Brazil, Guyana, Orinoco, and Venezuela when living in their natural habitat. Nevertheless, most of these fish sold in the market are artificially bred. They are a peaceful, easy-to-care-for, and tough species, which makes them an excellent option for beginners and experienced aquarium owners.

Size and Growth Rate


The Adult X-ray Tetras are typically only about 2 inches long and don’t need a lot of room in a fish tank. These fish reach sexual maturity between five to eight months old, indicating that their growth mainly happens during their first year of life.

Various factors, including nutrition and water conditions, influence the growth rate of Pristella tetra. Providing a varied diet to these fish is essential for their overall growth and development. Including high-quality fish food, flakes, and frozen or live food can contribute to their rapid growth.

In addition to nutrition, maintaining good water conditions, such as proper temperature and pH levels, is also crucial for the healthy growth of Pristella tetra. Regular water changes and a well-maintained aquarium environment can ensure optimal growth and vitality for these beautiful fish.


The majority of the fish’s body appears to be silver and mostly see-through, allowing its organs to be visible as it swims. Despite having some noticeable color and shine, it is commonly known as the x-ray tetra or x-ray pristella tetra due to this uncommon feature.

Apart from the translucent body, the remarkable characteristic of this fish is the color pattern on its fins. The dorsal and anal fins are distinguished by three bold stripes of vivid yellow, solid black, and sharp white. The yellow stripe is adjacent to the body, while the black stripe is positioned in the middle.

Pristella tetras have distinctive stripes and tailfins that range in color from reddish to pinkish. The degree of redness may differ among individual fish, with some having a hint of yellow at the base of their tails.

Pristella tetras are a type of tetra fish that has a large body with a thick midsection. Female Pristella tetras are typically more robust than males, and it’s easy to identify the sex when they lay eggs. During spawning, it’s possible to observe the eggs developing, which helps distinguish between male and female.


If you provide the pristella tetra with a suitable diet and excellent living conditions, you can anticipate their average lifespan to be approximately four to five years.

It is impossible to accurately calculate the lifespan of a fish due to numerous influencing factors.

Taking good care of your pristella tetra can significantly impact its overall health and reduce the likelihood of severe health issues. Also, purchasing these fish from a reliable source can improve their chances of thriving.

Tank Size and Setup

The Pristella Tetra, also known as the X-Ray Fish, is a deep-bodied tetra species that requires a suitable tank size and setup to thrive. To accommodate these active schooling fish, a tank size of at least 10 gallons is recommended, although it is better to provide a larger tank, around 15 to 20 gallons if possible.

The tank should be heavily planted with live or silk plants, driftwood, and rock caves for hiding spaces. A sand substrate is ideal, and adding dried leaves and natural-looking decor will help recreate their natural habitat.

Keeping the water conditions stable with a reliable and accurate water testing kit is crucial for their well-being. Overall, a well-decorated tank with moderate lighting and a good current will provide the optimal environment for the Pristella Tetra.

Water parameters

Maintaining the correct water parameters is crucial for the well-being of Pristella Tetras. These freshwater fish thrive in temperatures ranging from 74 to 82 degrees Fahrenheit. They prefer a pH level between 6.0 to 7.5, with a broad range of water hardness from 4 to 8 dH.

As they are adaptable to various water conditions, they can handle slightly brackish water, making them unique among Characins. However, sudden fluctuations in water conditions should be avoided to prevent stress and health issues. Investing in a reliable and accurate water test kit to regularly monitor and maintain these parameters is essential.

Aquarists can ensure the overall health and vitality of their Pristella Tetras by providing ideal water conditions.


Pristella Tetras produce waste and excrete ammonia, which can harm their health if not properly removed from the water. A good filtration system will help remove these waste products and any excess food or debris in the tank. This will help to maintain a clean and healthy environment for the fish.

In addition to a quality filter, it is also recommended to have a good water circulation system in the tank to ensure that all tank areas get proper filtration and oxygenation. This can be achieved through a powerhead or additional circulation pumps. It is also essential to monitor water parameters regularly and perform water changes to maintain a healthy and stable environment for the tank’s inhabitants.


Proper lighting is essential for the well-being of Pristella Tetras in the aquarium, and it’s crucial to give them a suitable light source since they do best in moderate lighting conditions.

LED lights are popular among aquarists as they offer a natural, energy-efficient lighting solution. These lights should be set up to mimic the fish’s natural habitat, providing a balance of light and shade.

Avoiding excessive lighting is essential, as it can cause stress and discomfort for the fish.

Water changes

Maintaining the water quality in your Pristella Tetra (X-Ray) aquarium is crucial for the health and well-being of your fish. Regular water changes are an essential part of this maintenance routine.

Removing a portion of the old water and replacing it with fresh, conditioned water can effectively remove any build-up of toxins and waste products. Ideally, you should perform a 25 percent water change every two weeks. This frequency allows removing harmful substances without causing unnecessary stress to your fish.

Additionally, monitor the water parameters regularly, including temperature, pH levels, and water hardness, to ensure they remain within the acceptable range for Pristella Tetras.

Following these guidelines can help create a clean and stable environment for your X-Ray Tetras to thrive.

Diseases and Prevention

Although Pristella Tetras are relatively resilient regarding water conditions, they remain vulnerable to contracting fish illnesses caused by parasites and bacteria.

One effective disease prevention method is maintaining a clean and well-maintained tank environment. Regular water changes, proper filtration, and stable water parameters can greatly reduce disease risk.

Additionally, it is essential to avoid introducing sick or stressed fish into the tank, as they can potentially spread diseases to the other tank inhabitants.

Proper nutrition and a balanced diet are essential to promoting the fish’s overall health and immune system.


Feeding recommendations

Their omnivorous nature makes them very easy to cater to when feeding pristella tetras. Their diverse diet includes live, fresh, and flake foods. For a well-rounded diet, it is recommended to feed high-quality flake foods as the primary source of nutrients.

These can be supplemented with occasional high-protein snacks such as freshly hatched brine shrimp, freeze-dried or frozen foods like bloodworms, and other similar options.

Feeding them two to three times a day is essential, giving them only enough food to consume within three minutes. This will prevent overfeeding and maintain optimal tank conditions.

Types of food

Commercial flakes or pellets should comprise the main part of their diet, providing balanced nutrition. However, offering them high-protein snacks to mimic their natural diet is also a good idea.

They enjoy hunting for insect larvae, and small bugs in the wild, so providing live or frozen foods like brine shrimp, bloodworms, and daphnia can be beneficial. Additionally, you can supplement their diet with chopped green vegetables.

Tank Mates

Suitable tank mates

These peaceful fish do well with species of similar temperament and size. Householding them with gentle, non-aggressive fish is best to ensure a harmonious tank environment.

Some suitable tank mates for Pristella Tetras include Pencil Fish, like Molly Fish and Ember Tetras. These species share similar water parameters and can coexist peacefully in the aquarium.

By carefully selecting compatible tank mates, you can create a beautiful community aquarium that showcases the unique elegance of these.

Unsuitable tank mates

While peaceful and easy-going, they’re incompatible with aggressive and semi-aggressive species. Large fish may mistake them for food, so stick to species of the same size.

Avoid overcrowding in the tank, which can lead to stress and health issues for the Pristella Tetras. Some unsuitable tank mates include cichlids and any aggressive or territorial fish.

You can create a harmonious and thriving aquatic community by selecting suitable tank mates.



Breeding behavior

Regarding breeding behavior, Pristella Tetras are relatively easy to breed in captivity. It is best to keep a separate breeding tank and start with a pair rather than a group, as this increases the chances of successful breeding.

The breeding tank should be at least 10 gallons and have the appropriate spawning environment, such as fine-leaved plants or dried leaves. The pH levels should be kept between 5.5 to 6.5, and the temperature should be steady to induce reproduction.

Covering the filter inlets with sponges is essential to prevent the Tetras from going where they shouldn’t. If all goes well, the female will lay 300 – 400 eggs in the plants or leaves, and they should hatch within 36 hours. The fry should be fed infusoria for the first few days and then gradually transition to small live or frozen foods.

Breeding setup

Breeding Pristella Tetras requires a separate breeding tank to ensure the best conditions for successful breeding. A tank size of at least ten gallons is recommended to provide enough space for the breeding pair and their eggs. The water temperature should be maintained at around 78 degrees Fahrenheit, and the pH level should be near-neutral.

Adding fine-leaf plants to the tank will provide hiding places for the eggs and fry. Covering any filter inlets with sponges is also essential to prevent the adults from eating the eggs. Once the female lays the eggs, transferring the adults back to the main tank is best to prevent them from consuming them.

The eggs will hatch within 24 to 36 hours, and the fry can be fed infusoria initially before transitioning to baby brine shrimp or similar foods.

Creating the proper breeding setup will significantly increase the chances of successful breeding for Pristella Tetras.

Final thoughts and recommendations.

Pristella Tetra (X-Ray) is a low-maintenance freshwater fish that adds beauty to any tank with its transparent body and vibrant fins.

These hardy and adaptable fish make them suitable for beginner and experienced aquarists.

Setting up a tank requires enough space and hiding places for the fish. Plants and driftwood are essential to create a natural habitat.

Pristella Tetras are peaceful and need good water and food for their health. They can live with other non-aggressive species of the same size.

The Pristella Tetra is a fantastic fish in your aquarium; it will thrive for years with the proper care.