Paracheirodon axelrodi – Cardinal Tetra
The Cardinal Tetra has been officially described in 1956 by Schultz als Paracheirodon axelrodi. This species has several synonyms: Cheirodon axelrodi and Hyphessobrycon cardinalis.
De naam Paracheirodon kun je opbreken in twee stukken: “Para” betekend bijna of onecht en houdt zoiets in als lijkt op. “Cheirodon” betekend puntige paal en is een verwijzing naar de puntige tanden van dit geslacht. De soortnaam “Axelrodi” is een verwijzing naar de auteur Herbert R. Axelrod.
Their common name is Cardinal Tetra. They owe this name to the cardinal red color on the underside.
Description
The difference between male and female Cardinal Tetra is very hard to see. They both have a fluorescent blue horizontal stripe running from their beak to their tail. Below this blue line runs a bright red. The fins are colorless and the back and belly are silver-colored. The males are slightly smaller than the females and the females have a more rounded belly than males. They look very similar to their cousin Paracheirodon innesi or Neon Tetra.
Thanks to its gentle character and behavior and its beautiful colors, it can be combined with many other species in a community aquarium. We don’t recommend Angelfish, as Angelfish are hunters and Cardinal Tetras are a natural food source.
The life expectancy of a Cardinal Tetra in the wild is about 1 year. In the aquarium, they can reach an age of up to 5 or even 10 years.
Biotope
The Paracheirodon axelrodi has a very large distribution area in Venezuela, Colombia and Brazil (Rio Negro, Rio Orinoco, Rio Vaupes Rio Aturia and their tributaries). They usually occur in small shady clear water or in black water streams. They populate the middle part of the water in usually large schools.
Diet
In the wild Cardinal Tetra feed mainly on meaty foods like invertebrates, eggs, and small insects like ants, mites, larvae and small young fish. Everything that moves and fits in their small beaks will be eaten. Alongside the meaty foods they will pick up some algae as well.
It is therefore very important to give Paracheirodon axelrodi (or any other fish) different kinds of food. With a varied diet of flake food, small living foods like Daphnia, and freshly hatched brine shrimp they stay healthy and show their best colors.
The Aquarium
Undoubtedly the Cardinal Tetra or Paracheirodon axelrodi is the most common species kept in aquariums. In the aquarium, it shows its best colors under some dimmed lighting or floating plants and adequate shelter. It is a schooling fish so you will need a minimum of 8 of them. The larger the school the more they show their natural behavior! They will school better if they feel threatened, so adding one of the larger but peaceful species makes them form a school but make sure they don’t get eaten.
They will do fine in a water temperature of 23 to 29 degrees Celsius. Just make sure not to keep them year-round at the minimum or maximum temperature as this will shorten their lifespan. Use a decent aquarium thermometer to check your heater.
Susceptibility to Diseases
It is a species that is very sensitive to Ich and changes in the water composition, often they are the first fish that get this disease if something goes wrong with the water quality. When moving this species definitely use the drip method to get them used to the new water composition.
Breeding Paracheirodon axelrodi
Breeding the Cardinal Tetra is very difficult and only reports of incidentally successful spawns can be found.
Use a breeding tank with very soft water with a pH of 5.5 to 6.0. Decorate the aquarium with Java moss and little lighting. The eggs hatch after a day, and the fry swim around after a few days. Cardinal tetras are egg scatterers, remove the parents after spawning or else they eat the eggs. The young Paracheirodon axelrodi can be raised with the smallest food like Paramecium.
In the wild, the Cardinal Tetra spawns during the rainy season. Mating usually takes place at dusk. The male hugs the female, while she releases the eggs the male releases his sperm and fertilizes the eggs. Up to 500 eggs are simply released into the river. Because Paracheirodon axelrodi eggs are sensitive to light, they are released into the shaded areas of the river.
Video
Author
Coby – J. de Lange
Copyright images
J. de Lange
Peter Maguire
Jennifer O. Reynolds
