More info
Datasheet
| Minimum Tank Size | 40 litres / 10.57 US gallons |
| Maximum Size | 1.6cm / 0.63inches |
| Temperature | 20°C / 68.00°F - 27°C / 80.60°F |
| Hardness | 1.01dgH / 18ppm - 12.05dgH / 215ppm |
| pH | 6.0-7.5 |
General Description
Microdevario Nanus, sometimes known as the 'green dwarf rasbora' or 'nana rasbora', is a peaceful schooling fish with a distinct black blotch at the tip of the dorsal fin and a greyish marking at the tip of the anal fin. Belonging to the Cyprinidae family, this species showcases miniaturization as sexually mature adults typically grow to less than 20mm in SL. It is best maintained alone or with similarly-sized species, and a group of 8-10 individuals is recommended for a more natural and visually appealing display.
Aquarium Setup
To replicate its natural habitat, it is advisable to set up a densely-planted tank with gentle filtration. Adding floating plants, driftwood roots, or branches to diffuse light is appreciated by M. nanus. The ideal water conditions include a pH range of 6.0-7.5, a temperature between 20-27°C, and a hardness of 18-215ppm. A minimum tank size of 40 litres is suitable for this species.
Behaviour
M. nanus is a schooling species by nature, displaying its best colors when competing for female attention. While peaceful, it is recommended to keep them in groups to reduce nervousness and enhance their natural behavior. This species can be compatible with certain small fishes from Myanmar, such as Celestichthys choprae and Brachydanio species.
Feeding and Diet
In the wild, M. nanus likely feeds on small invertebrates, algae, and zooplankton. In an aquarium, they accept dried foods but thrive on live and frozen options like Daphnia and Artemia. Providing a varied diet ensures their nutritional needs are met, contributing to their overall health and vitality.
Reproduction & Dimorphism
While breeding M. nanus in captivity is less common, success has been achieved with its close relative, M. kubotai. They scatter their eggs among aquatic vegetation and do not show parental care. Mature females are larger and deeper-bodied than the brightly colored males. A controlled breeding approach can help increase fry yield, with fry typically appearing 3-4 days after hatching.
Habitat and Distribution
Endemic to the lower Sittaung and Bago river drainages within the Irrawaddy Delta region, M. nanus inhabits sluggish and standing freshwater environments like rice paddies, swamps, and weedy ponds. The region experiences varying water levels throughout the year, with natural waterways and oxbow lakes providing suitable habitats for this species.