The rose danio (Danio roseus, Brachydanio rosea) is a tropical fish of the family Cyprinidae. At first glance, this species resembles the pearl danio but lacks the orange stripe on the side. It has a rosy coloration along the lower part of the fish and lower fins and gleams purple-blue in sunlight. It is also commonly known as the purple passion danio. Its natural range includes the Mekong River drainage in China, Thailand, Laos, and Myanmar.
Common Names: pearl danio, rose danio, Danio roseus
Origin / Habitat: Mekong River drainage in China, Thailand, Laos, and Myanmar
Care Level: Rather Easy to Moderate
Adult Size: Maximum length 1.25 inches or about 3 cm
Life: around 2-3 years
Tank Size: 10 gallon
Water Parameters: the pH of 6 -7.0
Water Hardness: 36 – 268 ppm
Temperature: Between 68-77 °F or 20-25 °C
Feeding: Will accept flake floods, pellets, and live foods such as bloodworms and daphnia.
Compatibility: Peaceful but fast, like most danios; needs plenty of space to swim; a good “dither” fish (draws timid fish out of hiding)
Minimum dimensions of the aquarium: 90x40x45h cm because it must be kept in groups of at least 8-10 specimens and is a very active species.
It does particularly well in a well-planted setting, with a dark substrate, and in bare or sparsely furnished settings, it appears faded and unattractive. The most suitable setup is designed to resemble a flowing river or stream, with a substrate of gravel and rocks of varying sizes and some large boulders smoothed by water. Movement pumps can be used to increase the current. This species appreciates slightly, but without exaggerating. Even if it is possible to find them in the rapids, they occupy the most peaceful and marginal areas, sheltered from the strong current.
Roots, branches, and robust aquatic plants, such as Microsorum, Bolbitis, and Anubias, can also be added, grown attached to furnishings.
The aquarium must be well covered as members of this genus are excellent jumpers and can pass through surprisingly small spaces.
Behavior and Compatibility
This species is very peaceful indeed and is ideal for well-appointed community aquariums. Because they do not have particular water chemistry requirements, they can be combined with many of the most popular fish, including other small minnows, tetra, poeciliid, rainbow fish, anabantoids, catfish, and loaches.
As always, when selecting a compatible fish community, research is essential, and their small adult size must be taken into consideration, as well as their liveliness and relentless movement, which can stress quieter fish.
It is a herd by nature and should be kept in a group of at least 8-10 individuals. Breeding them in decent numbers will make the fish less nervous, but it will give them a more effective and natural look, while the males will display their best colors to compete with each other for the females’ attention.
ref – https://en.wikipedia.org/wiki/Rose_danio