Pristella Tetra (X-Ray) 101: Care, Diet, Size & More | 2024

By: Martin McAdam
Updated: April 11, 2023

The Pristella Tetra, also known as the X-Ray Tetra, is a unique new fish discovered in late 2006 and introduced to the aquarium hobby shortly after that.

They were named “Pristella” (Latin: Pristis = saw) because of their three pairs of long teeth, and they were given the species name “X-Ray” because of their transparent (x-ray-like) bodies.

This tetra is a peaceful omnivore that will not bother other tank mates with its small size. However, it may be nippy towards any larger or long-finned fish (Neons and Guppies, for example) because they like to claim territories, and these smaller tetras are less likely to challenge a larger fish.

As with all tetras, they need to be kept in schools of 6 or more and will do their best when they have several companions of the same species. If you keep them in this manner, they will not only school but also shoal and swim throughout the aquarium.

In this article, we will see everything there is to know about the Pristella tetra. We will discuss their appearance, their diet, their behavior, how they breed, etc. So please keep reading!

Pristella Tetra: Species Summary

Scientific Name:Pristella maxillaris
Common Name: Pristella Tetra, X-Ray Tetra, Crystal Tetra, Glass Bloodfin.
Family: Characidae characin
Lifespan:4 to 5 years, possibly longer
Size:Up to 2 inches (5 cm) long.
Care Level:Easy to moderate
Origin:South America, Colombia , Peru
Social Behavior:peaceful & Non-aggressive
Water Conditions:72° – 82° F
Hardness Level:4-8dKH.
pH level:5.8 – 8.5
Minimum Tank Size:10- Gallons
Feeding:Omnivorous; accepts flakes and most prepared foods.

Most Pristella Tetras have a greenish/gray/silver body coloration with a faint dark horizontal stripe running from the top of their head to the lower body just in front of the anal fin. The dorsal, pelvic, pectoral, and anal fin is transparent.

The gill covers have a dark vertical stripe with precise outer edges in the center. The dorsal, pelvic, anal fins and upper body bases are marked in an iridescent blue that changes color depending on viewing angle or lighting conditions.

Their habitat is in the Upper Orinoco River system in South America. Pristella tetras originate from the very fast-moving waters of the Rio Negro.

The Pristella Tetra is one of the easiest tetras to keep, and they are perfect for a beginner. They can tolerate a wide range of water parameters, especially pH, and they do well in tropical community aquariums with other non-aggressive fish.

Pristella Tetra: Appearance

The Pristella Tetra has a translucent silver-white body with three distinctive black bands. The first band runs through the eye,

the second band is at the base of the caudal fin and extends to about halfway along the fin, and the third is a dark stripe that begins between the eyes and then travels to near the dorsal fin.

Pristella Tetra Appearance

These fish are beautiful when they are in good condition, and best of all, they are schooling fish and, therefore, very active in the aquarium.

Pristella Tetras are small fish, growing to only about 2 inches long. They are torpedo-shaped and have a vibrant green body with an orange stripe that runs the length of their body.

They also have three pairs of long, saw-like teeth on their mouths. They are striking unique-looking fish!

Pristella Tetra: Lifespan

In ideal conditions, most tropical fish live five years. Their lifespan is extended when they are kept in a community aquarium with many plants, rocks, and things to explore.

They will not survive long if kept in a small goldfish bowl or similar environment. They are generally only about 2 inches, so they are suitable for many aquarium setups.

Pristella Tetra: Size And Growth Rate

The Pristella Tetra is about 2 inches long in adulthood, although they can grow up to 3 inches when full-grown. They are slower-growing than most other tropical fish,

so they will not quickly outgrow your aquarium. Provide an adequate tank and watch the water parameters for their maximum size! They are small schooling fish, so do not keep them in tanks smaller than 10 gallons.

Pristella Tetra: Behavior

Pristella Tetras are some of the easier fish to care for because they are peaceful, but they like their school. Keeping only one or two Pristellas in your 10-gallon tank will be stressful for them. They like their schools and love having at least six other companions to swim with.

Pristella Tetra Behavior

The Pristella Tetra is a schooling fish and should be kept in a school of 6 or more. They are generally shy, peaceful fish that can do well with nearly all other non-aggressive tropical fish.

Pristella Tetra: Social Temperament

Pristella Tetras are very peaceful and can live with most non-aggressive community fish. However, if they are not kept in a school of at least 6, they might be too timid to swim around and explore their aquarium habitat.

While they do school and need companionship, keep an eye on them to ensure they aren’t becoming too stressed or aggressive with their tank mates. However, when kept in large schools, they become very active and entertaining to watch.

They will not bother any tank mates except other tetras since they are also schooling fish.

Pristella Tetra: Breeding

Pristellas are egg-layers that breed in warm, still water. If they become sexually mature (they will develop breeding tubes), the females will release eggs once they sense a male nearby.

Pristella Tetra Breeding

The male will fertilize these eggs before they fall to the bottom of the aquarium and cling together in clumps. A female can lay up to 300 to 400 eggs.

To breed Pristella Tetras, you must provide them with an aquarium of 10 to 15 gallons. Also, ensure the water is warm (78° to 80°) and still, or they won’t be able to spawn.

Pristella Tetra: Gestation Period

Pristellas give birth to live, free-swimming young after a gestation period of approximately 2 to 3 weeks. They have between 1 and 10 babies at a time. When born, the babies are fully formed and immediately eat whatever food they can find.

Pristella Tetra: Reproduction

The Pristella Tetra is a difficult fish to breed in the home aquarium. They spawn on overhanging branches and plants near the water’s surface in their natural habitat. They do not usually breed well in captivity because they must pick up specific environmental cues.

Pristella Tetra: Food & Diet

Pristella Tetras are omnivorous fish, which means they eat meat and plants. In the wild, you can see them eating insects on land and stranded fruit after it falls into the water. This is why they are considered opportunistic feeders in captivity.

They will happily take a flake or pelleted food formula for omnivores. They are not fussy eaters and enjoy brine shrimp, bloodworms, or any other small treat.

Pristella Tetra: Care

Pristella Tetra Care

All the necessary conditions for the care of pristella tetra are described below.


Pristellas are active swimmers but can usually be kept in a community tank with most other non-aggressive fish. They should not be housed with more significant or aggressive types of fish since the Pristella Tetra is relatively small and may become food for other animals in your aquarium.


Pristella Tetras do not require much water movement, and you should prevent the flow from being too strong since these fish like very calm waters. A low-end canister or box filter will suffice for this type of tank.


A light is not necessary for the Pristella Tetra. Since the Pristella is tiny, it does not need powerful lighting. If you have live plants in the tank, stronger lights may be necessary to encourage growth.


Pristellas can thrive in temperatures between 74°F and 82°F with a pH level between 6.0 and 8.0; they generally do best at an even 76°F. They are tropical fish that require warm water and should only be introduced to a tank heated evenly to these temperatures.


The Pristella Tetra does not usually interact with the substrate material, and it is recommended that gravel or pebbles not be used in its tank. These decorations can harm the Pristella if swallowed errantly and provide no benefit to the fish.

Tank Size

Pristella Tetras will thrive in a 10-gallon tank, but they do not like to be cramped. They need plenty of room to make sure they keep healthy and stress-free. Ensure that there are at least 5 gallons per fish in the tank when considering what size tank to purchase.

They also prefer a tank with a cover as these fish can be jumpers, and it is safe for them and good for the aquarium environment. Just ensure that you have enough filtration in your tank to provide for the number of fish you have.

Water Requirements

They can do well in a pH range of 5.5 to 8.5 and a temperature range of 64° to 82°Fahrenheit (21° to 28° Celsius). Since they are such schooling fish, choosing the median as their optimal tank condition is best.

Tank Region

Pristella Tetras like to be kept in the middle to bottom of their aquarium but still require access to the surface so they can breathe air. They are not very picky about where they have their bedding or swimming space.

Tank Pests

Pristella Tetras are not particularly susceptible to common aquarium diseases in the home aquarium setting. However, they can become stressed by changes in diet, pers commensurate with any change in environment.

Tank Conditions

Pristella Tetras are generally very hardy fish but can become stressed if their water is maintained correctly. When kept in warmer water with fluctuating pH levels, they are slightly more susceptible to disease, so it is best to keep the tank conditions stable.

Tank Shape

While they will do well in most setups, consider adding hardy plants and driftwood to the tank. These fish will also enjoy having a lot of hiding places, so make sure their tank has plenty of live or silk plants to dart in and out from.

Tank Decorations

In addition to being a very active fish, the Pristella Tetra is also an excellent jumper. Ensure your tank has a lid or canopy so they do not jump out of their aquarium and injure themselves.

Decorations should be firmly placed since these fish can be interested and give, and you do not want them injured from trying to explore a tall plant. They also do well with gravel and mulm since they enjoy sifting through and looking for goodies.

Hard Water

If your water has a lot of minerals in it or if you use reverse osmosis (RO) water, make sure to perform regular water changes to keep their environment stable.

Also, consider dechlorinating your tap water before adding it to the tank to increase the safety of your aquarium.

Adding hard water (water with a high mineral content) can cause your Pristella Tetras to be at risk during mating and egg-laying. If you notice their coloring starting to fade or they do not look as healthy, perform a 25% water change and use treated water.

Pristella Tetra: Potential Diseases

Diseases are not usually a significant concern for Pristella Tetras, who live in well-maintained aquariums. However, they can become stressed if their water conditions fluctuate too much.

Fish are resilient creatures, but turning your beautiful aquarium into a death trap only takes one mistake. Some diseases can be treated easily while others cannot – do your research before purchasing any fish.

An outbreak of skin flukes can send your Pristella Tetras into shock, killing them within hours. Watch for clamped fins and lethargy as the first signs that something may be wrong with your fish. With proper treatment, the Pristella Tetra should make a full recovery.

Pristella Tetra: Treatment And Medication For Diseases

Many diseases can be treated with aquarium salt and activated charcoal. For severe cases, antibiotics may be required.

If you catch any disease early on, it is best to perform frequent water changes to keep the water chemistry stable so you do not get stressed or ill.

Be aware that some medications can remove beneficial bacteria from your tank, causing your biological filtration to crash and making it crucial that you perform massive water changes to bring the chlorine/Chloramine down to 0ppm before adding more fish.

How To Control Pest In Pristella Tetra’s Tank?

Since they are such small fish, controlling pests in the Pristella Tetra’s tank is not usually difficult. The fish are small enough that most bugs are large enough to be avoided easily, but you can also use a freshwater dip or chemical treatments to keep your water clean.

Pristella Tetra: Tank Mates

Pristella Tetras can be kept with most other non-aggressive community tropical fish. They are generally very peaceful but will become stressed if they are not kept in a school of at least 6 individuals. If you decide to keep them with other tetra species, research first because some tetras can coexist well with Pristellas, while others may become too competitive.

Tetras are schooling fish and should ideally be kept in groups of 6 or more. In general, tetra species can school together. Best tank mates include other tetras such as the Ember Tetra, Glowlight Tetra, Convict Cichlid, Serpae Tetra, Black Neon Tetra, Danios, and White Cloud Mountain Minnows. In addition, larger fish with slower metabolisms may be able to tolerate a Pristella swimming among them.

Pristella Tetras can be kept with other fish species as long as the fish are not aggressive or too large. Smaller barb species make good tank mates, but you should research compatibility before putting them together.

Advantages of Having Pristella Tetra In Your Tank

  • Easy to care for: Pristella Tetras requires minimal care.
  • Colorful: Pristella Tetra has an orange body with iridescent blue/green scales to create a beautiful contrast.
  • Peaceful: Pristello Tetras can be housed with most community fish, but ensure they are not harmed.
  • Spines: Pristella Tetras have long spines on their dorsal fin to protect themselves. The tank must be covered to avoid injuries to the other fish living with them for this exact reason.
  • Active: This tetra species is active during both day and night, making this fish an excellent display for any aquarium.
  • Intelligent: Pristella Tetras school together and swim to the top of the tank when food is present.
  • Human-like: These particular tetra species can come closer to a human than other tetra species because they do not have as many teeth and will not nip your finger.
  • Social: Pristella Tetras form groups in the wild and enjoy being around other fish.
  • Unique: Some unique characteristics set this tetra species apart from others – for better or worse.
  • Unusual Fins: The fins on a Pristella Tetra have a comb-like quality.

Before purchasing Pristella Tetras, you must ensure the ideal water conditions for this species. Hard water is okay, but keeping their environment stable can also be problematic if your local water supply has high mineral content.

If you are experienced in keeping aquariums, you should have no problem with this fish. If you are new to the fish world, make sure you do your research before obtaining any fish for your tank.

Disadvantages Of Having Pristella Tetra In Your Tank

  • Sensitive to temperature changes: Pristella Tetra is a tropical fish that must be kept in water between 75-84 degrees Fahrenheit.
  • Cannot handle freezing weather: If exposed to below 50 degrees Fahrenheit, the Pristella Tetras will go into hibernation and may even die if exposed for too long.
  • Prone to disease: Pristella Tetra may become ill if the water temperature is not kept stable, they are overstocked, or there is some other stressor in their tank.
  • The tendency towards boredom: If left alone for too long, this fish will become bored and resort to bickering.
  • Prone to nipping: This fish is a bit of an aggressive feeder and may nip at your fingers if you have open wounds or the tank is not adequately covered.
  • Sensitive to chemicals: Certain types of medication can harm this breed – constantly research any products before using them with Pristello Tetras.
  • Does not get along well with others: When purchasing your Pristella Tetras, it is best only to purchase a group of 3 to 5, but if they must be kept with another species, they will most likely do better when grouped with similar-sized, peaceful species.
  • Prone to disease: Pristella Tetra is a tropical fish, and they are susceptible to sudden changes in temperature – any change can cause them to become ill.
  • Sensitive to water quality: If the tank is not adequately cared for, this fish will get sick quickly or may contract fin rot.
  • Prone to nipping: This fish is a bit of an aggressive feeder and may nip at your fingers if you have open wounds or if the tank is not adequately covered.
  • Poor community fish: If left alone for too long, these fish will become bored and resort to bickering amongst themselves.
  • Prone to disease: Pristella Tetra may become ill if the water temperature is not kept stable, they are overstocked, or there is some other stressor in their tank.


Pristella Tetras are very peaceful fish that will not bother any tank mates. They are also very active swimmers, darting all over the place and helping clean your aquarium by eating leftover food or algae from decoration.

Pristella Tetras are always a good option for small and large aquariums alike. They add a lot of energy and personality to the tank and will help keep it clean! On top of that, they are easy to care for and can live up to 3 years in optimal conditions.

If you want a beautiful, peaceful tropical fish that keeps your tank exciting and lively, try adding a Pristella Tetra to your next aquarium!

They are inexpensive at only a few dollars, and you can often find them at local fish stores. They take care and patience but are generally easy to care for once their specific needs are met.

Thanks for reading.

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