Neon green rasbora

Geographic Origin and Biotope: Southern Thailand (Ranong province) and Myanmar. Inhabits tiny mountain streams shaded by pristine rainforest, characterized by clear waters and mixed bottoms of mud, pebbles and branches.

Taxonomy and Morphology: Neon Green Rasbora (Microdevario kubotai). Dwarf Cyprinid (Microrasbora). Barely reaches 2 centimeters (0.8 inches) in total, showing a semi-transparent and tapered body of a micro-swimmer.

Social Behavior: Peaceful miniature gregarious. To be kept exclusively in dense schools of at least 15-20 specimens to induce group cohesion (shoaling) that will dart in unison through the plants.

Coloration and Sexual Dimorphism: "Neon Green" coloration, among the rarest in freshwater fish. A bright and reflective phosphorescent green (or lime green) metallic stripe runs along the transparent flanks. Mature females have a much rounder belly than the slender males.

Aquarium Setup: The king of Nano-Aquariums and advanced Aquascaping (30-60 Liters / 8-15 Gallons). Loves Iwagumi style lawns (Glossostigma or Hemianthus callitrichoides) mixed with Seiryu stones. Intense lighting will maximize the bright green.

Diet and Feeding: Obligate micro-feeding. The mouth is so tiny that it cannot break normal flakes. Use micronized powders (e.g. for fry), brine shrimp nauplii or micro-granules <0.5mm to be dropped in the column.

Water Quality: Very demanding on maintenance. The chemistry (Ph 6.5) must be kept stable and the water free of pollutants (Nitrates always below 10ppm). The filtration must be oversized for nano-aquariums, but the flow must be gentle so as not to blend the fish.

Compatibility and Tankmates: Do not place in standard community tanks (they would be food for any fish larger than 5 cm / 2 inches). Ideal companions: Caridina (Red Cherry Shrimp), Boraras brigittae, Corydoras pygmaeus, or Otocinclus.

Aquarium Reproduction: Egg-scatterers. They release micro sticky eggs in Java Moss daily. Parents (if fed enough) often ignore the eggs, allowing mature nano-aquariums to see fry appear "spontaneously".

Risks and Diseases: Predation and Malnutrition. They are very often paired, with supreme ignorance, to Betta fish in shops. Bettas, being ambush predators, will exterminate the entire green school overnight. Struggle to feed in crowded tanks.