Diamond Tetra: Care, Tank Mates, Size & More!

Have you been looking for a stunning and hardy fish to add to your aquarium? Look no further than the Diamond Tetra!

With its shimmering scales and striking coloring, this beautiful fish is popular for many fish enthusiasts.

But before you run out to purchase one, learning about their care requirements, tank mates, and size is important.

In this blog post, we’ll cover everything you need to know about Diamond Tetras so that you can provide the best home for your new underwater friend.

Species Summary

The diamond tetra, scientifically known as Moenkhausia pittieri, has a striking appearance, which is why it goes by so many other names – diamond characin and timanttitetra.

It hails from South America and can be found in many of the region’s slow-moving and shallow tributaries – including the Rio Bue, Rio Tiquiriti, and Lake Valencia.

The diamond tetra is a popular choice among aquarists all over the world. It is a hardy fish and does well in captivity, so it’s a common sight in the fish-keeping hobby.

Average Diamond Tetra Size


Diamond Tetras are known for their eye-catching appearance and sparkling scales. With an average size of 2.4 inches, they are larger than most other Tetras. However, they still have the same flat laterally-compressed body shape and the long dorsal and anal fins characteristic of Tetras.

Male Diamond Tetras tend to have longer and pointed fins, while females have shorter dorsal fins and are slightly rounder. These differences make it easy to identify a Diamond Tetra’s sex.


Diamond tetras have an average lifespan of three to six years in captivity, although this depends on the care the owner provides.

While these fish are hardy and resilient, a well-maintained environment and optimal diet are necessary to keep them healthy and prevent disease. Proper care can also extend their lifespan, and owners should be aware of their general health and well-being.

Although there is no guarantee for a fish’s lifespan, providing a stable and comfortable environment can greatly improve their chances of living a long life.

Factors such as stress and overcrowding can lead to a shorter lifespan, highlighting the importance of appropriate tank size and compatible tank mates. Diamond tetras are a great option for beginner aquarists as they are easy to care for but still need proper attention and care.

Owners should take the time to research and understand the needs of their fish to ensure they live long and healthy life.


The diamond tetra is a sturdy fish with a larger-than-average body that’s still laterally compressed. It’s named for its shimmering scales that reflect orange, blue, green, and gold colors. The iridescent sheen becomes more vivid as it matures – a sight to behold!

The fins of this species are semi-transparent and tinted a gentle violet hue. The males have pointed, elongated dorsal fins, while the females’ fins are shorter – this makes it easy to discern the sexes during the breeding season.

The eyes of the diamond tetra are also quite remarkable – the upper half of each eye is splashed with a glimmering red hue, adding to the fish’s overall beauty. It’s a small but noteworthy detail that will catch your eye even when the fish is swimming.

Diamond Tetra Care

Diamond tetra care is fairly simple. These freshwater fish are quite strong, making them an ideal choice for novice aquarists and experienced hobbyists alike.

However, some essential guidelines must be considered to ensure your fish remain healthy and reach their full potential.

Once you understand their needs, taking care of them is a breeze!

Tank Size

Diamond tetras are small, peaceful freshwater fish that prefer to be kept in schools. When considering tank size for diamond tetras, it is important to remember their small size and active nature.

A minimum tank size of 15 gallons is recommended for a small group of three fish, but more space is always better.

Providing ample swimming space and hiding spots with plants or decorations will help keep the fish secure in their environment. Diamond tetras are adaptable to various water conditions, but maintaining a well-maintained and stable environment will help keep them healthy and happy.

As with any fish, the tank size should also consider potential tank mates. Diamond tetras can be good community fish when kept with others of similar size and temperament.

Overall, a well-maintained tank with plenty of space and comfortable hides will keep these beautiful fish content and thriving in their home.

Water Parameters

Diamond tetras are freshwater fish that require specific water parameters to thrive. The ideal temperature for these fish is between 72 and 82°F, the pH level should be between 6.0 and 7.5, and the water hardness should be between 5 and 15 dGH.

Maintaining consistent water quality is important to prevent the fish from becoming stressed or ill. Weekly water changes of 25% to 50% will help to keep the water clean and healthy.

It’s also important to avoid overfeeding the fish, as uneaten food can quickly contaminate the water. A good rule of thumb is to feed the fish only what they can eat within two to three minutes.

Adding live plants to the tank can help to absorb excess nutrients and improve water quality.

Diamond tetra owners need to prioritize the maintenance of proper water parameters to ensure their fish’s health and well-being.

Setting Up Their Tank

When setting up a tank for diamond tetras, it’s important to give them plenty of places to hide and relax. This can be accomplished by adding a variety of foregrounds, tall stems, and floating plants. These plants should provide adequate shelter from bright lights, as the fish don’t do well when exposed to too much light.

Filtration is also necessary for a healthy tank. Hang-on-back models and canister models are suitable and should be able to circulate the water multiple times each hour to keep ammonia and nitrate levels low.

In summary, diamond tetras need plenty of cover from the light and a strong filtration system. When you combine the right plants with a good filter, your fish can thrive in their environment.

Potential Diseases

Diamond tetras are hardy fish that can handle various water conditions. However, like all fish, they are susceptible to diseases that can harm or even kill them.

The first thing to do when preventing disease is to keep their environment clean, which means regular water changes, maintaining proper filtration, and avoiding overcrowding in the tank.

Diseases affecting diamond tetras include ich, fin rot, and cottonmouth.

  • Ich is a parasitic disease that sudden changes in water temperature, poor water quality, or stress can cause. Symptoms include white spots on the body and fins and excessive scratching.
  • Fin rot is a bacterial infection that can be caused by poor water quality, overcrowding, or injury to the fins. Symptoms include frayed and discolored fins.
  • Cottonmouth is a fungal infection caused by poor water circulation or high levels of organic matter in the tank. Symptoms include a white or gray cotton-like growth around the mouth or gills.

It’s essential to quarantine any new fish before adding them to your tank to prevent the spread of disease. If you notice any signs of illness in your diamond tetras, it’s best to remove them and treat them in a separate tank to prevent the spread of the disease.

Seeking advice from a veterinarian or experienced fish keeper can help ensure your fish stay healthy and happy.

Food & Diet

Diamond tetras enjoy a varied diet, which is important to their health. They are omnivores and will eat meat-based and plant-based foods.

Good quality flake food is a great staple for their diet. However, you should also offer them live or frozen foods such as brine shrimp, daphnia, and bloodworms. These types of food will provide your Diamond tetras with essential protein and help keep their diet varied.

You should provide them with small amounts of food two to three times a day. This ensures that they receive enough nutrition and prevents overfeeding, which can lead to unhealthy living conditions and water quality issues.

Avoid letting the food settle on the bottom of the tank when feeding. Uneaten food can quickly decompose and cause health problems for your fish. Removing any uneaten food within a few minutes of feeding time is important.

By providing your Diamond tetras with a well-balanced diet and regular feeding schedule, you’ll help them thrive and flourish in your aquarium.

Behavior & Temperament


Diamond tetras are known for their peaceful and calm demeanor. These freshwater fish spend their days swimming together in groups, searching for food and occasional playful roughhousing. They are active during the day and rest at night, preferring around eight hours of darkness.

Diamond tetras are good community fish and mix well with other fish of similar size and temperament. They thrive when kept in schools of six or more and are less likely to become stressed or aggressive toward other fish.

However, diamond tetras can become semi-aggressive if they feel threatened or stressed and may nip the fins of other fish. Owners can avoid this by making their diamond tetras feel secure with other diamond tetras for a company and providing plenty of vegetation for hiding spots.

These freshwater fish also prefer the middle or bottom of the tank and enjoy being in the open in their school, provided there is enough plant coverage to dart behind when needed.

Diamond tetras are easy to care for and resilient, ideal for beginners and novice aquarists. They require a well-maintained environment, a top-notch diet, and proper care to stay healthy and reach their full potential.

Tank Mates

Diamond tetras are social fish that thrive in a community tank with other peaceful species. However, choosing tank mates that can tolerate the same water conditions as the diamond tetra is essential.

Compatible species include other tetra species, rasboras, guppies, cory catfish, and celestial pearl danios. It is important to avoid keeping diamond tetras with larger or more aggressive species, as they may become stressed or injured.

Additionally, adding some live plants to the tank can provide hiding places and improve the community’s overall health.

Maintaining a well-balanced and varied diet for all fish in the tank is also important for their overall health and happiness.

Diamond tetras can live in a peaceful and thriving community tank by carefully selecting compatible tank mates and providing adequate care.


Breeding the diamond tetra can be a moderately easy process, but the most significant challenge is finding compatible pairs. Each fish should be the same size and age, so it may take multiple attempts to get the right match. The majority of unsuccessful breeding attempts are due to mismatched pairs.

You will need a separate spawning tank to get many fry. A 20-gallon tank between 79 to 84° F is recommended. You can add java moss or spawning mops to give the females a place to lay the eggs. Meshworks, too, since the eggs can fit through, but the parents will be kept out.

For the best results, the water should have a hardness of 4° dGH or lower and a pH of 5.5 to 6.5. An air-powered filter is also essential. You may prepare the fish in separate tanks before breeding by feeding them a diet of live foods for a week or more.

When it’s time to start breeding, you can transfer an appropriate pair or group of six fish of each sex into the tank. Males should be brightly colored, while females will have rounded bellies with eggs.

You can start with a dark tank to induce spawning and slowly increase the light levels. Spawning could take one to two days, or it might happen immediately. The males will follow the females and fertilize the eggs after release.

Once spawning has occurred, removing the parents is important to prevent them from eating the eggs. The eggs will hatch in 24 to 36 hours, and the fry will start swimming around three to four days later. Fry can eat algae like infusoria for the first few days and then brine shrimp, nauplii, or microworms.

Diamond tetra fry grows rapidly and will resemble an adult in size within a short time. However, they won’t have the same coloring as adults for nine months.


Diamond tetras are a captivating freshwater fish that all owners should consider.

Not only are they incredibly beautiful, but they also have very simple care requirements, making them perfect for any fish enthusiast!

If you still have any doubts about how to care for diamond tetras, feel free to let us know. We are more than willing to assist you in any way we can!