Blue Danio

 Quick Care Facts

• Care Level: Easy   • Temperament: Peaceful   • Maximum Size: 2"
• Minimum Tank Size: 10 gallons   • Water Conditions: 73-78° F, KH 5-12, pH 6.5-7.5
• Diet: Omnivore   • Origin: Thailand   • Family: Cyprinidae
• Species: Danios   • Aquarium Type: Community

Help Support AquariumDomain!      

• Your support keeps AquariumDomain advertisement free, lightning fast and fully optimized for both mobile and desktop browsing.

• Visit our Patreon page to learn about the exclusive benefits our Patrons receive!

Blue Danio (Danio kerri) originate from the slowly moving streams, tributaries and floodplains of southern Thailand. Both wild specimens and farm raised specimens are available to aquarium hobbyists fairly often. Blue Danio are sold under a variety of common names including: Blue Danio, Turquoise Danio, Danio kerri and Brachydanio kerri.

The natural habitat of the Blue Danio is comprised of clear shallow water, gravel and rocky substrate and sparse submerged vegetation. Despite their natural habitat lacking dense submerged vegetation Blue Danio do very well in planted aquariums, as their small size and fluid swimming motion allow them to move effortlessly in and out of even the most densely planted aquariums.

The Blue Danio is also one of the species whose appears benefits greatly from an aquarium with dark substrate and dense plantings, as this helps to bring out the much sought after blue coloration in the fish. The overall hardiness of the Blue Danio makes it suitable for beginning aquarium hobbyists and for a wide range of aquarium sizes and decor.

The Blue Danio is a peaceful schooling species that does well in any peaceful community aquarium setup. They should be kept as a group of at least 6 individuals both to provide them a sense of security and because they are much more attractive when swimming in a tight group. In fact it is the ability of a group of Blue Danio darting in and out of dense vegetation that makes them such an impressive site within the aquarium. Tank mates should consist of other peaceful to semi-aggressive community fish species that are not large enough to see the Blue Danio as food.

While not overly demanding in terms of water chemistry, aquarium size or decor, Blue Danio will prefer an aquarium that has clean well oxygenated water and moderate to strong water currents. With their relatively small adult size of just 2 inches and small biological impact, Blue Danio make an excellent schooling species for both larger and nano planted aquariums.

In nature Blue Danio utilize their upturned mouths to feed on small insect larvae, worms, crustaceans and other similar prey that inhabit the shoreline and waters surface of their native streams. The bulk of their diet should come from meaty foods; however, they should also be provided commercial omnivore preparations, algae or plant based flakes.

It is best to feed them a mix of commercial carnivore and omnivore flake foods, while mixing in some freeze-dried or frozen worms, daphnia, cyclopeeze, brine shrimp or other similar food items. Providing a varied diet will help ensure that they receive all the vitamins and minerals they need to maintain a healthy immune system.

Sexing Blue Danio is similar to that of most Danio species in that the males are smaller and more slender, with the females being larger and significantly more rounded in appearance. Once the Blue Danio reaches its adult size of two inches the difference in gender is very easy to recognize, even to the beginning hobbyist. Blue Danio are prolific breeders and will readily spawn under a variety of aquarium conditions.

Hobbyists need simply keep a male and a group of females in an aquarium with a gravel substrate and quality water conditions for them to spawn. The female will scatter her eggs on the substrate, while the male will fertilize them. Once hatched the adults should be removed and the fry fed baby brine shrimp or finely chopped meaty food pieces.