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Diamond Tetra Must Know Care Facts, Behavior, Breeding

Diamond Tetra, also known as diamond characin, or the Timantti Tetra, is an eye-catching species less famous in the fish-keeping world. They have shiny scales that spark at the correct lighting like diamonds; hence, they are named Diamond Tetra.

They are easy-to-care fish that do better in soft and slightly acidic water conditions. They tend to live in groups that are fun to watch. 

In this guide, you’ll learn how to care for Diamond Tetras, their habitats, water conditions, tank size and decorations, feeding, breeding, and more.

What is Diamond Tetra?

Diamond Tetra is a freshwater fish found initially from inland bodies of water in South America. Diamond Tetras are typically found in the Rio Tiquiriti, Rio Bue, and Lake Valencia. 

Typically almost all the fishes found in this region do well in captivity, so is Diamond Tetras. Diamond Tetras are beginner-friendly fish that need low maintenance and live for several years when kept in good water conditions. 

Diamond Tetras are well known for their opalesque scales that are especially beautiful when in dim light. They are omnivores, Peaceful and schooling fish that stay in groups. Hence, you have to keep at least five fish in a tank to keep them happy.

Diamond Tetra scales

Scientific Classification of Diamond Tetra

  • Kingdom: Animalia
  • Phylum: Chordata
  • Class: Actinopterygii
  • Order: Characiformes
  • Family: Characidae
  • Genus: Moenkhausia
  • Species: pittieri

Diamond Tetra Appearance

Diamond Tetras are one of the largest tetra species out there, but they still feature the same laterally compressed body. They are stockier and more prolonged than many other tetra types.

Their scales feature a gorgeous finish with a silvery hue. Their iridescent shimmery scales can flash many colors like orange, blue, green, and gold. This pearlescent shimmer gets more vibrant when the fish gets mature.

The fins look semi-transparent and have a subtle violent tone. The anal fin is longer than other Tetra species.

Diamond Tetra

Male Diamond Tetras have a long and pointed dorsal fin, while females have a short dorsal fin. This difference makes them easy to understand their breed, which is helpful in breeding them.

Diamond Tetra’s eyes have a subtle splash of red on the upper half that is unique for Diamond Tetras.

Is Diamond Tetra Hardy?

Diamond Tetra is a moderately hardy fish species that can tolerate a variety of water conditions within reason. This hardiness makes them a good choice for beginner fish keepers.

How big does Diamond Tetra get?

Diamond Tetras grows up to 2.4 inches long. They are pretty smaller than many other aquarium fishes; therefore, you can keep them in a smaller aquarium.

Because of their small size, Diamond Tetras look like tiny glimmering torpedoes shooting around the tank, which is interesting.

Is Diamond Tetra aggressive?

Diamond Tetras are not aggressive. Diamond Tetras are peaceful fish that get along with any other fish species. These fish prefer to stay in small groups and will explore the tank everywhere and scavenge food. You might see some fighting here and there, but that is not related to aggressiveness. They are just playing.

Are Tetras Fin Nippers?

Tetras are fin nippers. Diamond Tetras love to chase each other and nip at suspecting tank mates. However, if you put more than eight fish in a tank and the tank is large enough to swim freely, they would not bother nipping at other fish as they get busy schooling with their own kind.


Diamond Tetras are schooling fish that stay in small groups. They are super active fish that swim everywhere in the tank. They are scavengers that explore the bottom of the tank for food and also very playful fish. 

Diamond Tetras are peaceful species that cohabitate with other fish easily. They prefer larger space, although they can live in smaller areas.

However, if overstocked with Diamond Tetras, they tend to show aggressive behavior and nip at other fish species. So, giving them a tank large enough is crucial if you plan to add any tank mates for Diamond Tetra.

Diamond Tetra Lifespan:

Diamond Tetras have a life span of between 3 to 6 years. If given good water conditions and proper care, they can live longer. However, there is no exact timeframe for Diamond Tetras’ lifespan.

Types of Diamond Tetra

In addition to the main Diamond Tetra color, there are three various types of Diamond Tetras on record.

  • Black Diamond Tetra – This is actually a variation of Neon Tetra. They got the name Black Diamond Tetra because of the black color shiny scales in their body. Otherwise, they are not related to Diamond Tetras.
  • Blue Diamond Tetra – Blue Diamond Tetra is a blue color variation of Diamond Tetra. There is another tetra called Blue Diamond Tetra, but it is actually Diamond Head Neon Tetra.
  • Long Fin Diamond Tetra – Male Diamond Tetras, have longer and pointier dorsal fins. Because of this reason, Male Diamond Tetras outshine female Tetras. Male Diamond Tetras are generally called Long Fin Diamond Tetra.

Diamond Tetra care

Care Level:Easy
ColorFlash colors like orange, blue, green
Lifespan3 to 6 years
Size:2 to 2.4 inches
Water temperature:72°F to 82°F
pH6.0 to 7.5
Water hardness 4 to 8 KH
Minimum Tank Size:15-20 gallons
How many for 20 gallon tankSmall school of 6+ tetras
Tank Set-Up:Freshwater with plants and wood
Community:Peaceful community
Diamond Tetra care sheet

Diamon Tetra Care is pretty straightforward. Diamond Tetras are a resilient species that makes them an excellent choice for novices.

However, there are some guidelines you should follow to keep Diamond Tetras. Knowing them will make it easier to stay healthy and happy fish in your Aquarium.

Diamond Tetra size

The average Diamond Tetra size is about 2 to 2.4 inches. Because of their small size, they are pretty easy to manage and care for.

Diamond Tetra Tank Size

Diamond Tetras live in groups. So, you have to keep at least 3 Tetras in a tank. For a group of 3 Diamond Tetras, you need to have at least a 15-gallon tank. As Diamond Tetras are schooling fish that explore everywhere, more space for your fish is never a bad thing. They will actually appreciate it.

How Many Should Diamond Tetra Be Kept Together?

As Diamond Tetras are schooling fish, you should keep at least three Tetras together. Otherwise, Diamond Tetras get stressed, which makes them prone to diseases.

Tank setup

Diamond Tetras are used to live in environments that are full of plants, just like their natural habitats. That being said, they will do well in the Amazonian Biotype setup.  So, feel free to do your best to replicate their natural habitat as much as possible.


You can use any substrate with Diamond Tetras because they don’t explore the substrate to scavenge food. But, it is best to use sand substrate because sand replicates their natural habitat. You can also add driftwood and twisting branches to provide wild hiding places for these species.


You are free to add as many plants as you want because Diamond Tetras love hiding places so much. You can mix foregrounds plants, tall stem plants, and floating plants in your Aquarium because Diamond Tetras don’t bother eating all of them.

Diamond Tetras don’t like bright light, so adding plants helps them take cover from the light as well as hide and relax.

Filtration System

Diamond Tetras can get along with standard filtration systems. You can utilize hang-on-back models or canister models. However, the filter should be able to cycle the water volume several times an hour to keep ammonia and nitrate levels undetectable.


Diamond Tetras prefer low, subdued lighting. They enjoy hiding in plants and other decorations. So, add shadowy, dark tank decorations to provide iridescence for this species.

Water quality condition

Diamond Tetras come from rivers and streams in South America. So, they prefer warm freshwater that is slightly neutral. They are hardy fish that can tolerate slightly acidic water. However, alkaline water can do a lot to help bring out their beauty!

Here are the water parameters you should keep in your Aquarium.

Water temperature: 72°F to 82°F (Ideal temperature – 75 to 76 degrees)

pH levels: 6.0 to 7.5 (lower is better for their appearance)

Water hardness: 4 to 8 KH

Note: Always keep a reliable and accurate aquarium test kit to check your water condition to ensure your fish do fine in your Aquarium.

You should perform 25% to 50% water change bi-weekly to keep the water condition at ideal levels. If the tank is densely stocked, more water changes will be necessary.

Special tips

While Diamond Tetras are hardy fish species that can tolerate different conditions, providing their natural habitat with ideal water conditions ensure they are stress-free and healthy. Feeding them a high-quality diet can guarantee they will thrive well in your Aquarium.

Diamond Tetra breeding 

Breeding Diamond Tetras is a complicated process. Pairing the fish is the most prominent challenge fish keepers face.

Diamond Tetras are very picky when it comes to breeding. They only spawn with other fish if they are also the same size and same age. They are egg-layers that lay eggs to the bottom of the tank. Once the female Tetra releases the eggs, they will fall into the mops to stay protected from hungry adults.

Before starting the breeding process, you should prepare the tank. Add some spawning mops or clumps of java moss to the bottom of the tank.

The water temperature of the breeding tank should be 79.0° F as Diamond Tetras needs a temperature between 79 to 84° F to start spawning.

The water Ph level should be pH 5.5 – 6.5 (soft and slightly acidic), and hardness should be 4° dGH or less. Also, you should add a small, air-powered sponge filter to provide gentle water flow and filtering water.

Before breeding, you should condition the male and female fish in separate tanks for about 7 to 10 days. Feed the fish a rich diet and plenty of small, live foods during this time. Choose more rounded females and most colorful males for breeding.

How To Breed Diamond Tetras

Below is the step-by-step system on how to breed Diamond Tetras.

Step 1: Turn all the lights off in the breeding tank and add your fish. You can add a single pair or about six fish couples into the tank. They will not bother by other fish.

Step 2: Once all of the fish are in, slowly raise the light level. This lighting change should induce spawning. The fish may spawn immediately or after a day or two.

Step 3: Remove all the adults after spawning. If not removed, the adults tend to eat the eggs. While spawning, females release their eggs while the males fertilize them.

The Diamond Tetra eggs will hatch in about 24 to 36 hours. The fry will survive in the egg sac for a few more days and start swimming in the tank. By now, you can feed them fry food like infusoria or baby brine shrimp.

Young Diamond Tetras have dull colorations than the adults. They will pick up the colors at about nine months of age.

Identify Female Diamond Tetra

If you plan to breed Diamond Tetras, you should be able to identify female Diamon Tetras first. However, it is harder to differentiate between males and females at their younger age. The fish need to be matured to distinguish female from male.

Male Diamond Tetras are larger in size and less stocky than females. Males have an elongated dorsal fin while the females are relatively short—the anal fin of females shaped like a hook.

Female Diamond Tetras show a more gravid appearance when they are ready to reproduce.

Diamond Tetra Male Vs. Female Differences

As we have explained above, male Diamond Tetras are larger than female ones. Female Diamond Tetras are more stockier than Males. 

Male Diamond Tetras have a longer dorsal fin than females. The female fish’s anal fin is shaped like a hook.

How Many Babies Does Diamond Tetra Have?

Diamond Tetra can produce around 30 to 60 eggs per clutch. So, you can expect about 15 (give or take) survived babies from each female fish.

How To Care for Fry

You should remove adults from the tanks as soon as the fish finish spawning to save fish eggs. Within around 24 to 36 hours, fish eggs will hatch. Fry stay in the egg for several days in the egg sac and then start to swim freely in the water.

When the fry is freely swimming, it’s time to start feeding them with fry food such as infusoria or baby brine shrimp. Fry needs several feedings per day, and when they slowly grow bigger, you can gradually change the diet to adult tetra food.

How To Feed Diamond Tetra?

Feeding Diamon Tetra is pretty straightforward. They are omnivore species that are easy to please with anything you feed. They are not picky eaters. Therefore finding a suitable meal is effortless.

What do Diamond Tetras eat

Diamond Tetras eat anything that is ingestible, including meat-based food and plant-based food. They are easy to please species that accept anything they will find to eat.

What do Diamond Tetras in the Wild?

Diamond Tetra eat small insects and spineless species living in the water and fall into the water. They also eat plant matters in the wild.

What to Feed Diamond Tetras in the Aquarium?

Diamond Tetras accept any food you offer. You can feed them with dry pellets and flakes. Additionally, you can serve frozen and live food such as Brine shrimp, blackworms, daphnia, and bloodworms. You can also feed Diamond Tetras with vegetables such as lettuce. However, the main diet should be omnivore pellet or flakes.

How Long Can Diamond Tetras Go Without Food?

Diamond Tetra is a small fish like guppies, mollies, and other smaller fish. Smaller fish can not go for more than one week without food. So, one thing you should remember is to feed them daily to keep them happy and healthy.

When to feed Diamond Tetras?

You should feed 2 to 3 times daily for about 3 minutes. As they are omnivore species, they will eat anything you provide and eat it fast, like starved to death. But, do not feed Diamond Tetras for more than 3 minutes if you want a cleaner tank.

How Much To Feed?

About 3 pellets per fish per feeding is enough as Diamond Tetras are small fish species. But, as you keep more than one fish in a fish tank, counting pellets is not a practical option. Instead, put some pellets on the water and watch until they finish eating. If they finish eating them fast, add some more until they eat for about 3 minutes. After that, take out the rest left on the surface of the water with a fishnet. Don’t leave leftover food in the tank as they will produce Nitrogen and Ammonia in the decomposing process.

What Fish Can Live With Diamond Tetra? Diamond Tetra Tank Mates

Diamond Tetras are an excellent addition to a community tank. They are peaceful and get along with other species well. However, you should be careful when choosing tank mates for Diamond Tetras.

You shouldn’t keep these fish with aggressive species. They will become a victim of nipping and attacking of aggressive fishes if kept together.

You should also avoid larger fish because they can easily become prey. If possible, avoid adding slow swimmers and slow eaters because Diamond Tetras can out-compete them for food.

The best tank mates for Diamond Tetras are same-sized peaceful fish species. Below is a list of good tank mates for Diamond Tetras.

  • Celestial pearl danios
  • Molly fish
  • Rasboras
  • Most tetra species
  • Guppies
  • Cory catfish
  • Peaceful bottom-dwellers

Diamond Tetra And Angelfish

Diamond Tetras and Angelfish can live together in a community tank. Angelfish are generally a peaceful cichlid that won’t bother other fish species unless they are their own kind. However, both fish species should be the same sized because if the size changes, one can become the other one’s prey as both fish species are omnivores.

Diamond Tetra and Shrimp

You should avoid adding shrimp to a tank that already has Diamond Tetras unless you want them to eat the shrimp. Diamon Tetras see the shrimps as a snack and will definitely eat the shrimp. So, Diamond Tetra and Shrimp are a big “No-No.”

Diamond Tetra And Betta

Diamond Tetra and Betta will be compatible tank mates if certain conditions are met. You need to add at least 8 Diamond Tetras into the tank to avoid their fin nipping behavior, and the tank should be large enough for 8 Diamond Tetras. So, the tank size should be at least 30 to 40 gallons to add 8 Diamond Tetras.

Diamond Tetra Diseases

Diamond Tetras are extremely hardy when it comes to fish diseases. Fish diseases are not a problem for Diamond Tetras in well maintained Aquarium.

But, there is no guarantee that they will not catch any diseases because your tank gets bacteria and other infections from anything you introduce to your tank.

To minimize the risk of facing any fish diseases, you should maintain a cleaner water condition and quarantine any fish or decorations you intend to add to your tank. 

The good thing about Diamond Tetras is that their resistance and resilience, which makes them prone to many fish diseases. When the tank faces an outbreak, only a few fishes get infected at first, and if you act quickly and take measures, you can limit the spreading of the disease.

The best way to prevent any fish diseases is to providing them a healthy environment and a well-balanced diet. Better if you provide an environment that resembles their natural habitats to lessen stress. Less stressed fish is always a happy and healthy fish. Stressed fish always catch diseases quickly.

Below is a list of common fish diseases Diamon Tetras get infected with.

  • Skin flukes
  • Parasitic infestations (protozoa, worms, etc.)
  • Ichthyobodo infection
  • Parasitic infestations (protozoa, worms, etc.)
  • Bacterial infections (general)
  • Bacterial diseases

Related Questions 

Full Grown Diamond Tetra Size

A full-grown Diamond Tetra Size Would be about 2.4 inches maximum. Diamond Tetras are smaller fish species that don’t grow much longer. That makes them a perfect addition to a smaller fish tank.

Diamond Tetra Eat Plants

Diamond Tetras eat plant matters, but they are not Plant Killers. They like to explore plants, so you should add as many aquarium plants in your Aquarium to provide them with a better environment.

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About Dr.Chamika

Hello, I'm Dr. Chamika. I am a Researcher in Water quality, Aquatic organisms, and Environmental chemistry. I am a passionate fish keeper, with10 years of experience. My mission is to help other aquarists experience the joy of fish keeping.