Bengal Danio (Devario devario)

The Bengal Danio makes a stunning addition to the community aquarium. They are hardy, very active and relatively peaceful. These Danios are not an aggressive fish but may upset timid, slow-moving tankmates with their constant activity and vigorous feeding behaviour. Therefore, it is most suited to larger aquariums containing robust, similarly-sized fishes.

Bengal Danios are a schooling species by nature, and you should ideally keep them in groups of 8 to 10 individuals. Maintaining them in decent numbers will make the fish less nervous and result in a more effective, natural-looking display. Since these fish are sociable, they do not fare very well if kept singly.

Any aggression will also be restrained as the fish concentrate on maintaining their hierarchical position within the group, and males tend to display better colours in rivals' presence.

The Bengal Danio is an elongated fish with a high-back and lateral compression. Their body is rounded, and they have no barbels. The colour varies depending on the population.

Their back and belly are golden-brown, and the flanks are blue with some subtle, transverse yellow stripes. They present a broad, dark blue bar on each side that extends from the rear part of the mid-section to the fork of the caudal fin. The fins are usually transparent.

Habitat

The Bengal Danio Originates from India, Nepal, Pakistan, Bangladesh and Afghanistan in South Asia. They inhabit the Indus and the Assam Rivers throughout as well as fast-flowing streams, floodplains and ponds where the vegetation is plentiful, and the substrates are composed of silt, sand, clay, cobbles and boulders.

Other Danios of interest

Diet & Feeding

In the aquarium, Bengal Danios are mostly unfussy and will accept most foods given to them. High quality dried products can be used as the staple diet. Still, it would be best to supplement this with regular meals of small live and frozen fares such as daphnia, bloodworm, artemia, and such, which will help your fish maintain their best colouring and condition.

Sexual Dimorphism

It is easy to differentiate male from female Bengal Danios. Males are typically slimmer, smaller, and far more colourful than females, whereas females are rounder bellied, less colourful and slightly larger than males.

Breeding

Bengal Danios will often spawn when in good condition and in a well-planted, established aquarium. Small numbers of fry may likely start to appear without any intervention. However, if you would like to increase the yield, a more controlled approach will be required.

You can still condition the group together, but you will need to set up a smaller aquarium filled with mature water. This should be dimly lit and the bottom covered with some mesh that has big enough size so that the eggs can drop through but small enough that the adults cannot get through.

Artificial grass matting or marbles can also be used as an alternative and works well. Providing fine-leaved plants such as java moss or spawning mops can again return satisfactory results.

The water needs to be slightly acidic to neutral, and you should raise the temperature by a few degrees. An air-powered sponge filter or air stone is also recommended to provide water movement and oxygenation.

Once the adults are well-conditioned and the females appear to be full of eggs, you should then introduce one or two pairs into the breeding tank.

Spawning usually takes place within 24 hours, where the female will suddenly appear noticeably slimmer, then 48 hours later you should remove the adults.

The incubation period is temperature-dependant to an extent but typically lasts around 24 to 36 hours the fry will then become free-swimming a few days after that.

Initially, it would be best to feed the fry on Paramecium or similar and then introduce artemia nauplii, microworm, dry food or powdered foods once the fry is large enough to accept them.

Frquently asked questions about the Bengal Danio

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