Exclamation Point Rasbora (Boraras urophthalmoides) Care Guide
One of the tiniest aquarium fish, this micro rasbora features a warm reddish body with a distinctive dark spot near the tail base followed by a thin line — resembling an exclamation mark.
Overview
Boraras urophthalmoides is a species in the family Cyprinidae. One of the tiniest aquarium fish, this micro rasbora features a warm reddish body with a distinctive dark spot near the tail base followed by a thin line — resembling an exclamation mark. Perfect for densely planted nano tanks, it is a peaceful schooling fish that thrives in soft, acidic water with minimal flow.
Taxonomy
- Family: Cyprinidae
- Genus: Boraras
- Scientific name: Boraras urophthalmoides
- Other names: Least Rasbora, Boraras urophthalmoides
- Origin: Southeast Asia
Habitat
Native to shallow, still and slow-moving waters of Thailand, Cambodia and Vietnam, including rice paddies and roadside ditches. Inhabits soft, slightly acidic water with dense vegetation. A nano-sized species of the genus Boraras named for the mark on its caudal peduncle.
Tank requirements
- Minimum tank volume: 20 L
- Temperature: 22-28 °C
- pH: 5-7
- GH: 1-8 °dGH
- Water flow: low
- Adult size: 1.5-2 cm
- Lifespan: 2-4 years
- Recommended group size: ≥ 10
- Difficulty: beginner
Diet
Classified as omnivore. Recommended feeding frequency: 2x daily. In captivity, offer a varied diet appropriate to the species — quality prepared foods supplemented with frozen or live items of suitable size.
Compatibility
- Temperament: peaceful
- Swimming level: middle
- Compatible tank mates: Chili Rasbora, Ember Tetra, Pygmy Corydoras, Cherry Shrimp, Otocinclus
- Avoid with: Any fish large enough to eat them, Aggressive species
Breeding
- Breeding strategy: egg-scatterer
- Breeding difficulty: intermediate