Description
Emerald Eye Rasbora (Brevibora dorsiocellata)
Overview
Brevibora dorsiocellata, commonly known as the eyespot rasbora, emerald eye rasbora, or hi-spot rasbora, is a small, peaceful freshwater fish from the Danionidae family (subfamily Rasborinae), native to slow-flowing blackwater streams and peat swamps of Southeast Asia, including southern Thailand, Peninsular Malaysia, Sumatra, and Borneo. Named for the distinctive black ocellus (eye-like spot) on its dorsal fin, it features a slender, silvery body with iridescent green-blue eyes and hints of green or red on the flanks and caudal fin in males during breeding. Growing to 3–4 cm, females are stockier with rounder abdomens. Endangered in the wild due to habitat loss, most aquarium specimens are commercially bred. Their tight shoaling Behaviour and delicate beauty make them ideal for nano or planted community tanks, though they are sensitive to water quality.
Care Requirements
Tank Size:
Minimum 60L for a shoal of 8–10; 75L or larger preferred for larger groups to support shoaling and reduce stress. Base dimensions of at least 60 x 30 cm recommended.
Water Parameters:
- Temperature: 20–25°C; avoid exceeding 28°C for long periods; 26–27°C optimal for breeding.
- pH: 6.0–6.5 (acidic; can tolerate 5.5–7.0 with peat filtration).
- Hardness: 2–12 dGH (soft water; TDS <150 ppm).
- Ammonia/Nitrite: 0 ppm.
- Nitrate: <50 ppm (ideally <15 ppm, as they are highly sensitive).
- Substrate: Fine sand or smooth gravel; dark substrates enhance colouration. Add leaf litter (e.g., Indian almond leaves) to mimic peat swamp habitats and release tannins.
- Décor: Dense low-light plants (e.g., Java moss, Cryptocoryne, Anubias) and floating plants for cover and subdued lighting. Include driftwood, twigs, or alder cones to replicate blackwater conditions. Ensure open swimming space.
- Filtration: Gentle flow (4–5x tank volume/hour) using sponge or hang-on-back filters with peat or blackwater extract to maintain acidic, tannin-stained water.
- Lighting: Low; floating plants and dim lighting mimic forest canopy shade.
- Other: Tight-fitting lid essential, as they may jump when stressed. Acclimatize slowly to avoid chemical shock.
Maintenance
- Water Changes: 20–30% weekly or 10–15% biweekly with dechlorinated water (using anti-chlorine agents) matching tank parameters to prevent nitrate buildup and pH swings.
- Tank Cleaning: Siphon uneaten food and debris; lightly vacuum substrate to preserve beneficial bacteria.
- Replace leaf litter periodically to maintain tannins.
- Testing: Weekly checks for pH, hardness, ammonia, nitrite, and nitrate using a reliable test kit to ensure stability, as they are prone to diseases like ich in poor conditions.
- Equipment Check: Ensure filters provide gentle flow, heaters maintain stable temperatures, and lid is secure. Monitor peat filtration to maintain acidity.
Diet
- Type: Omnivorous micro-predator; feeds on small invertebrates, worms, crustaceans, and plant matter in the wild.
- Foods:
- Dry: High-quality micro-pellets, crushed flakes, or granules (e.g., Fluval Bug Bites, Hikari Micro Pellets) as a staple.
- Live/Frozen: Daphnia, baby brine shrimp, cyclops, bloodworms, micro-worms (2–3 times weekly for vibrant colours).
- Plant-Based: Spirulina flakes, blanched vegetables (e.g., zucchini), or biofilm from leaves for variety.
- Feeding: Small portions 2–3 times daily, consumed within 1–2 minutes to avoid water fouling.
- Notes: Varied diet enhances colouration, especially males’ pinkish-red caudal fin during breeding. Their small mouths require fine foods. Grazing on tank biofilm supplements diet.
Behaviour and Compatibility
- Temperament: Peaceful but timid; active shoalers that may nip fins of slow-moving fish if stressed or in small groups.
- Social Behaviour: Strictly shoaling; keep 8–10 or more (1–2 females per male) to reduce stress and encourage natural schooling and male displays. Solitary or small groups (<6) become stressed, shy, and disease-prone.
- Compatible Tankmates:
- Small, peaceful fish: Neon tetras, celestial pearl danios, Trigonostigma spp., Pseudomugil spp.
- Bottom-dwellers: Kuhli loaches, pygmy Corydoras, Otocinclus catfish.
- Incompatible: Large or aggressive fish (e.g., cichlids, tiger barbs), slow-moving or long-finned fish (e.g., bettas, guppies), or Brevibora cheeya, which may show aggression toward B. dorsiocellata. Avoid mixing with other rasboras to prevent competition or hybridization.
- Notes: Dense vegetation and large shoals reduce skittishness. Males display pinkish-red caudal fins when competing for females.
Breeding Behaviour
Breeding Type: Egg scatterers; continuous spawners that scatter non-adhesive eggs over plants without parental care.
Picture for illustrative purposes only. Either come in store to view available stock or request pictures to be sent to you.
Please Note: Due to variations within species resulting from age, region, sex, etc., the actual livestock may not look identical to the image. Approximate size range may also vary between individual specimens.
