The Zebra Danio (zebrafish) is the most popular aquarium fish among the pet fish keepers. The zebrafish (Danio rerio) was first described by Francis Buchanan-Hamilton in 1822. The zebra fish helps to prevent mosquito control in their geographic region. It is a ray-finned fish under the Cyprinidae family of order Cypriniformes. It prefers to live most of the time in the middle and upper layers of the water body. It reaches sexually mature at the age between six to eight months. It is listed as `least concern` in the IUCN Red Data Book.
- Phylum: Chordata
- Sub-phylum: Vertebrata
- Class: Actinopterygii
- Order: Cypriniformes
- Family: Cyprinidae
- Sub-family: Danioninae
- Genus: Danio
- Species: Danio rerio
Distribution and Habitat
It is distributed in South Asian Countries such as India, Pakistan, Bangladesh, Nepal, Myanmar, and Bhutan. It prefers to live in slow moving to stagnant standing waters such as rice fields, rivers, streams, ponds, ditches, beels etc.
In addition to the main name, aquarists gave other affectionate nicknames, such as Zebra danio, zebrafish, or zebras.
Quick Zebrafish Facts
- Scientific name:Danio rerio
- Common name: Zebra danio
- Origin: South Asia
- Temperament: Peaceful
- Adult size: 5-7 cm
- Tank region: Surface to column layer
- Tank size: 10 gallons or larger
- Diet: Omnivore
- Breeding: Egg layer
- Water pH:6.5-7.5
- Hardness: 8-20 dGH
- Temperature: 65°F – 75°F (18°C – 24°C)
- Water movement: Weak
- Lighting: Moderate -normal
- Care level: Easy
- Life span: 3-5 years
Body Shape and Colors
The zebrafish has an elongated body with terminal small mouth. Body is yellow-green in color with 5-7 dark blue stripes along the body. The body has incomplete lateral line and two pairs of barbells. The young fins are short. But as they grow, they become veil. Fins give their owners an enchanting appearance. The edges of the veil fins may have a yellow color.
Males are more slender than females, and also have more intense colors. Females have a more rounded abdomen, especially after young stage.
Size and Lifespan
In wild, it can grow up to 7 cm in length but in aquarium condition the adult reaches around 5 cm in length. Life expectancy is about three years. Sometimes with good aquarium condition, it can live up to five years or more.
Housing and Care
The zebrafish is an unpretentious, peaceful, freshwater aquarium fish. In addition, it is easy to care for as your pet. In tank water, the pH should be closer to neutral with fluctuations in temperature from 15 to 30 °C.
The tank should be 5-10 gallons with plenty of space for swimming. The bottom should be covered with a layer of granite chips or small stones. Large river sand can serve as a ground.
The tank should also have long-leaved plants including Vallisneria, Eleocharis, Sagittaria, Cabomba, Myriophyllum. Plants must be planted along the back and side walls, leaving room for swimming. It is advisable to keep flocks of at least seven or ten fish.
The zebrafish is very active, restless and very fast fish. It can jump out of the aquarium. Therefore, a tank with these fish should be provided with a lid or at least covered with glass of suitable dimensions to prevent jumping out.
It is desirable to contain not less than 7-10 pieces. Danio rerio fish are compatible with virtually any other peace-loving fish with similar characteristics including other representatives of the genus Danio, guppies, swordfish, barbs etc.
Choosing the right food is one of the most important task to keep the fish healthy and alive. It is an omnivorous fish. It prefers to eat live food such Daphnia, Cyclops, Tubifex, insect, mosquito larvae and bloodworms. In captivity, it takes high quality flakes or pellets. It also eats zucchini and frozen brine shrimp and blood worms. To make your fish happy, feed should be given 2-3 times daily.
Reproduction also takes place without much difficulty. It spawns during the monsoon period which ranges from April to August. Therefore, no preliminary preparation is necessary.
About a week before spawning, the males should be separated from the females and kept separate from each other. The female from the male can be distinguished by a more rounded abdomen and less saturated color of the yellow-green stripes.
Before spawning, the brooders need to be fed abundantly, preferably with a meaty food. The breeding tank should be with a volume of 10 gallons. The tank should have the plants with small stones. The water must be fresh for at least 2 days. It is poured a layer of about 5 centimeters above the plants.
The temperature should be 24 – 26° C. In the evening, two males and one female can be put into the spawning tank. Spawning begins in the morning when the first rays of the sun fall on the spawning ground. The female can lay 50 to 400 eggs.
About 3-4 days later, larvae appear from the eggs, which hang on the banks’ glass for several days. They look like strings with thickened heads. A few days later, the fry begin to swim. At this time, the fry should be fed with infusoria, rotifers, newly born artemia (brine shrimp). After few days, young fry can take small crustaceans such as Daphnia, Cyclops. Young fry as they grow, it is necessary to transfer into a more spacious tank.
The male is smaller than the female of the same age. The male has yellow/gold stripes between the blue-black stripes on their flanks. The male also has larger anal fins than female. Female has rounded body than the males. It is particularly noticeable when she carries eggs in her belly.
The zebrafish is resistant to disease. Sometimes fish can become more susceptible to disease such as white spot disease (ich), Velvet, Neon Tetra Disease and Skinny Disease. To keep your fish healthy and disease free, tank environment should be maintained properly with regular water changes.
The zebra danio is the most popular aquarium fish due to its hardiness and brilliant color patterns. It is available in the local pet store with sensible costs. If you keep this fish in your aquarium, it will make your aquarium more appealing. We prescribe you to purchase this eye-catching fish from the well-known pet fish traders.