How Often Do Cardinal Tetras Reproduce?

Fish are relatively easy to care for and need lesser attention than other pets. As a result, the culture of fish keeping is outrageously increasing these days. Among the different beautiful fishes popular with aquarists, Cardinal tetra is a common name. One of the benefits of keeping them is these fishes are easy to breed. But how often do Cardinal tetras reproduce?

Cardinal tetras reproduce pretty often. Depending on their living conditions, these fishes can multiply anywhere from three times a year to six times a year. Therefore, if you keep your cardinals in a smaller tank, they will reproduce more often than if you kept them in more giant tanks.

Hopefully, you have a good understanding of the different types of freshwater fish and their needs. Today, we will be focusing on cardinal tetras and answering one of the most common questions we get: How often do cardinal tetras reproduce?

How Do Cardinal Tetras Reproduce?

Cardinal tetras, a widespread freshwater fish species, reproduce sexually by laying eggs. Like other members of the family Characidae, cardinal tetras have an egg spot on their anal fin.  This spot helps differentiate between females and males once they mature enough.

Male cardinal tetras develop a red spot on their anal fin, and females will have no such place. Once the fish mature sexually at around eight months, they reproduce in one male with multiple females. The female releases her eggs into the water for fertilization by the male.

After fertilization, cardinals dig a pit in the substrate and bury their eggs. And several fins protect these eggs. The male guards the eggs until they hatch, usually three to four days later.

How Often Do Cardinal Tetras Reproduce?

Cardinal tetras (Paracheirodon axelrodi) are freshwater fish belonging to the characin family of fishes. The cardinal tetra has a long iridescent blue body with red caudal and anal fins. Thus, people call it the “cardinal.”

Usually, Cardinal tetras reproduce pretty often. But this is dependent on their living environment.

Ideally, aquarium water should be around 25 degrees Celsius for reproduction. It should also contain soft, slightly acid to neutral pH levels with a smooth gravel or sand substrate for easy burrowing during spawning periods. This habitat type will provide the best breeding pairs in larger tanks.

Cardinal tetras reproduce at least twice a year in their natural environment. But they can breed more if conditions are right. In the aquarium, breeding is pretty straightforward and does not require any special conditioning or treatment of the parents to induce spawning.

When Do Cardinal Tetras Reproduce?

Cardinal tetras must be at least three months old before they can reproduce.

Cardinal tetras will breed during the warmer spring and summer seasons, though this can vary based on location. The cardinal tetra is a tropical fish that prefers temperatures between 24-28C (75-82F).

The female lays her eggs among plants or other surfaces in open water. The male will then fertilize them externally.

The eggs are black in color and hatch after 36 hours or more, depending on the temperature of the water. Therefore, it would be best to feed the fry with a diet that includes infusoria for at least two weeks before introducing them to newly hatched brine shrimp which they can eat immediately.

How Many Eggs Do Cardinal Tetras Lay?

Cardinal tetras lay around 40 eggs per clutch. The female will attach the fertilized eggs to plants in the aquarium to keep them safe until they hatch. During that time, she is responsible for turning over the plant material every few days so that her young get fresh food and water.

How Often Do Cardinal Tetras Lay Eggs?

Cardinal tetras lay eggs around once per month. Therefore, the female will release her young when they are about five weeks old. And this means she can have up to four batches of fry in a given year. However, she may need time between the first three or four of these batches. It is because too frequent laying might exhaust her and cause death due to the stress.

How To Breed Cardinal Tetras At Home?

Cardinal tetras are a popular fish species among home aquarists. In addition, they can be great additions to community aquariums and smaller tanks because they live in groups of six or more and don’t need too much swimming space.

When it comes to breeding them at home, there isn’t an established way to breed cardinal tetras. However, it is possible to encourage them into spawning by providing the right environment and food.

Generally speaking, most fish species will reproduce when they are between 12-18 months old or have a length of about three inches for guppies and mollies. In addition, proper water conditions and hiding spots are also crucial for reproduction.

Cardinal tetras generally reproduce in groups. Thus, it is best to keep them in tanks to accommodate six individuals. A larger tank also provides them with enough space to swim around. The same goes for food because cardinal tetras need high-quality flake food to stay healthy.

Things To Consider When You Are Breeding Cardinal Tetras:

For a healthy and sustainable breeding tank, there are certain things you need to consider. The things include:

  • Provide a suitable tank with optimal water conditions for breeding cardinal tetras.
  • Maintain the pH level in an ideal range between four and six. Also, maintain proper carbonate hardness levels (KH) within this same range to prevent diseases from developing. Two degrees below or above these levels may cause stress to your cardinals.
  • Keep track of the temperature in your breeding tank. The ideal temperature for these fish is 76 to 83 degrees Fahrenheit (24-28 Celsius). Anything below or above this range may cause stress and affect their reproductive behavior.
  • Provide ample hiding spots within the tank to feel secure enough to breed without disturbance from other fish species in the aquarium.
  • You must have a source of light to view the courtship and mating. A flashlight works well for this purpose. The cardinal tetra fish will be more visible under bright lights.
  • The breeding tank should measure at least 20 gallons (75 liters) per pair. But 30 gallons (115 liters) is even better. Although, you can also go with a smaller tank as long as it has suitable water parameters and hiding spots for the cardinal tetra fish to breed successfully.


Overall, cardinal tetras are beautiful fish that add life to any aquarium. Of course, you can breed them in captivity. But their breeding is complex, and experienced breeders should only attempt it with high-quality equipment. Nevertheless, the fish are relatively hardy and not very demanding, considering their beauty.

But to reproduce, cardinal tetras need a lot of space and food. So you cannot keep them in a large tank with lots of plants and hiding places. In addition, the water should have a high level of oxygen and be soft to very hard.

Hopefully, this article answered your question of how often do cardinal tetras reproduce.

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