Pristella Tetra (X-Ray) Tetras 101: Care, Lifespan, Facts & More!

Pristella Tetra (X-Ray) Tetras

Pristella Tetras are a fish that is native to South America. They are a small fish, only reaching a maximum size of 2 inches. 

These fish have a silver body with black stripes and a bright blue stripe that runs along the length of their body. 

They are also known as X-Ray Tetras because they have translucent scales that allow you to see their internal organs. 

In this guide, we will discuss everything you need to know about Pristella Tetras including their diet, care, and habitat.


Scientific NamePristella maxillaris
Common NamePristella / X-Ray Tetras, Golden or Gold Pristella Tetra, or the Water Goldfinch.
OriginNative to the coastal rivers of South America
Minimum Tank Size10 gallons
LengthTypically about 2 inches long 
DietOmnivorous and will eat both plant and animal matter
Ease of CareBeginner
pHFrom 5.8 to 8.5 (Between 6.0 to 7.5 is perfect)
TemperatureBetween 64°F and 82°F (about 75 degrees) 
BreedingEgg layers
Lifespan4 to 8 years

Pristella Tetra Origins

The pristella tetra, also known as the Pristella maxillaris, is a South American fish.

It’s recognized for its X-ray-like translucent body and hardy mentality, which has made it a popular choice for freshwater aquariums worldwide, despite being indigenous to Brazil, Guyana, Orinoco, and Venezuela.

These species that belong to the Characidae family migrate seasonally, moving with changes in the environment and floods.

However, they are very adaptable in captivity and can live alongside other freshwater fish.

What Are the Features of Pristella/X-Ray Tetra?

1. Appearance & Colors

As their name suggests, pristella tetras are mainly silver and translucent, allowing you to see their internal organs.

Pristella species are best known for their translucent bodies and light metallic gold coloration. They also can be pretty colorful, with bright dorsal, pelvis, anal, and caudal fins.

The fish has three yellow, black, and white vertical stripes on its dorsal and anal fins.

They also have crimson or pinkish tailfins in addition to eye-catching stripes.

The redness of each fish varies somewhat. A touch of yellow may be seen at the tail fin’s caudal fork.

2. Length

The average length of a Pristella tetra is around two inches, with some individuals growing up to only 1.75 inches.

3. Weight 

X-Ray Tetra has an average weight of 1.4 grams. In some rare cases, some species may weigh 2.0 grams. 

4. Lifespan

The typical lifespan of a pristella tetra is four to five years, though there are no ways to determine a fish’s life expectancy precisely.

Far too many factors come into play. With the proper diet and top-notch living conditions, you can help your pet enjoy a long and healthy life.

Is Pristella/X-Ray Tetra Hardy?

Pristella tetras are relatively easy to care for and make a great addition to any aquarium. They are hardy fish that can withstand a wide range of water conditions and tolerate changes in water quality.

However, like all fish, they are susceptible to disease and should be monitored closely for any signs of illness.

Pristella/X-Ray Tetra Availability

These little guys are super popular due to their unique appearance and relatively easy care requirements.

But what many people don’t realize is that X-Ray Tetras are pretty difficult to find in the wild. They’re only found in many streams and rivers in South America, which makes sense when you consider their unique appearance.

The X-Ray Tetra is one of the few freshwater fish that can see through its body! This adaptation allows them to spot predators and escape danger quickly.

If you’re looking to add some X-Ray Tetras to your aquarium, you’ll need to research first. These fish are not commonly available in pet stores. Your best bet is to find a specialty retailer or order them online.

How to Care for Pristella/X-Ray Tetra?

1. Tank Size

Pristella tetras are schooling fish that are active. They prefer to stick together and explore their surroundings as a single entity.

While each may appear tiny individually, you must accept a group of at least six.

We recommend a tank that is at least 15 to 20 gallons if you want to maintain a healthy school of pristella tetras. They’ll have the room they need to swim and explore without being crammed.

2. Temperature

Pristella tetras are tropical freshwater fish originating from South America.

They prefer water temperatures between 64-82 degrees Fahrenheit, with an ideal temperature around 75 degrees.

3. PH Level

This fish prefers water with a neutral pH level. So, they will thrive in an aquarium with a pH level between 5.8 and 8.5.

This fish is not sensitive to changes in pH levels, but it is essential to maintain a stable environment for your fish.

 If you are keeping Pristella/X-Ray Tetras in your aquarium, it is essential to test the water regularly and ensure that the pH levels are within the ideal range.

4. Lighting

While pristella tetras can adapt to a wide range of lighting conditions, they prefer dimmer lighting. Too much light can cause stress and make them more susceptible to disease.

So, to keep pristella tetras in your aquarium, provide them with a dimly lit environment.

5. Filters

As you know, keeping your tank water healthy and clean is essential for the health of your fish.

But did you know that the type of filter you use can also play a role in keeping your tank water clean?

If you’re looking for a filter that will keep your Pristella tetra’s tank clean and healthy, you’ll want to consider a filter specifically designed for use with these types of fish.

Here are some things to look for in a good Pristella or X-Ray tetra filter:

  •  A filter that uses charcoal to remove impurities from the water.
  •  A filter with a flow rate that is appropriate for the size of your tank.
  •  A filter that is easy to clean and maintain.
  •  A filter that is affordable and will last for many years.
  •  A filter that comes with a warranty from the manufacturer.

When you keep these things in mind, you’ll be sure to find a filter that will work well for your Pristella or X-Ray tetra’s tank.

6. Tank Decoration

As we mentioned, Pristella tetras are native to South American rivers, where the environment is ever-changing.

In captivity, it’s essential to recreate their natural habitat as closely as possible. This means adding plenty of plants, driftwood, rock caves, and more to your tank.

Start with a layer of the sand substrate. Spread it evenly and use it to anchor some live or silk plants.

Live plants are always best, as they can improve water conditions. Utilize a variety of species like Java fern, Amazon swords, and more.

Driftwood, rock caves, and plenty of plants will recreate the natural habitat of your pristella tetras and make them feel right at home.

Pristella/X-Ray Tetra Diet

The Pristella or X-Ray Tetra is an omnivore, which means it will do well on a diet of good-quality flakes, brine shrimp, and even frozen bloodworms.

To ensure your Pristella’s nutrition isn’t lacking, you can also try feeding it small insects or insect larvae to keep its protein levels up.

What’s surprising, though, is that X-ray Tetras like to be fed multiple times a day. Most aquarium keepers will feed them twice or three times a day. Only give them enough food to consume in three minutes at each feeding.

Pristella/X-Ray Tetra Compatibility

Pristella tetras are a calm species that may live in harmony with other freshwater tank inhabitants, such as the same species.

You should have no difficulty keeping them together in your aquarium if your tank mates have a similar temperament.

Pristella/X-Ray Tetra can be kept with the following fish:

  • Small Tetras (like the ember)
  • Apistogramma
  • Pencil Fish
  • Small Types Of Rasboras
  • Guppy Fish
  • Most Loaches
  • Molly Fish
  • Platy Fish

Pristella/X-Ray Tetra Predators:

  • Aggressive like cichlids
  • semi-aggressive species

Pristella/X-Ray Tetra Gender Difference

When it comes to Pristella or X-Ray tetras, you can quickly tell the difference between males and females.

For one, females are generally larger and bulkier than males. You’ll also notice that the female’s body is more round, especially around the midsection.

Additionally, when these fish are spawning, you can see the female’s eggs develop. This makes it simple to tell which fish is which sex.

Thus, if you’re looking to breed these tetras, it’s essential to know how to identify each gender.

Pristella/X-Ray Tetra Breeding

Pristella tetras are one of the easiest fish to breed in captivity. These fish migrate to the flooded savannahs to breed among plants in their natural habitat. Fortunately, recreating those migratory conditions isn’t too tricky with a separate breeding tank.

Here are some tips for successfully breeding pristella tetras:

  • The breeding tank should hold at least ten gallons.
  • Keep the temperature around 78 degrees Fahrenheit and the pH balance near-neutral.
  • Add fine-leaf plants to give the eggs and fry a place to hide.
  • Make sure to cover any filter inlets with sponges as well.

Once your breeding tank is set up, you can introduce a pair of pristella tetras.

These fish are not aggressive and will generally get along with others of their kind. However, it’s best to have just one male and one female when it comes to breeding.

The female pristella tetra will lay her eggs on plants or other surfaces in the tank.

Once she has laid her eggs, the male will fertilize them. The eggs will hatch in about 24-48 hours.

The fry (baby fish) will be tiny and vulnerable when they first hatch. They will need to be fed tiny live or frozen foods.

After a few weeks, they can transition to a diet of brine shrimp, bloodworms, and other small live foods.

Possible Diseases and Prevention

Pristella tetras are among the hardiest aquarium fish. They can withstand a wide range of water conditions and are very tolerant of changes in water quality.

However, like all fish, they are susceptible to disease and should be monitored closely for any signs of illness.

Fin rot

This is a bacterial infection that affects the fins and tail of the fish. Fin rot symptoms include redness, swelling, and loss of fin tissue.


Use antibiotics if the rotting is jagged. You can also use antifungal medication if the rot is more evenly spread out and the fin has holes.


Columnaris is a bacterial infection that affects the fish’s skin, gills, and fins. Symptoms include redness, ulcers, and fin loss.


External infections should be treated with antibiotics, chemicals in the water, or both.

1 Copper sulfate, Acriflavine, Furan, and Terramycin may be used in the water to treat columnaris.

Terramycin has proven to be quite effective both as a bath and when used to treat foods for internal infections.


Ich is another common disease affecting your fish. This parasitic infection is caused by a single-celled organism called Cryptocaryon irritans.

Symptoms of ich include white spots on the fish’s body, lethargy, and loss of appetite.


The most simple therapy is to visit your local pet store and purchase an Ich treatment.

Most are created with formaldehyde, malachite green, copper sulfate, or these compounds. Hikari Ich X is The best treatment.

Last Words

Pristella/X-Ray Tetra is a peaceful fish that become a fantastic companion if you know how to look after them. Give it a go if you’re interested!

We hope you enjoyed this article as much as we did. If you have any questions, please share them with us in the comment section below.