Description
Neon Dwarf Rainbow fish (Melanotaenia praecox)
Overview
Melanotaenia praecox, commonly known as the dwarf neon rainbowfish, is a small, vibrant freshwater fish from the Melanotaeniidae family, native to the clear, slow-moving rainforest streams of the Mamberamo River system in West Papua, Indonesia. Named for its iridescent blue body and neon-red fins in males, it grows to 5–8 cm, with females displaying duller silvery-green hues and yellow-orange fins. Its peaceful, active shoaling nature and compact size make it ideal for planted community tanks, though it requires pristine water and stable conditions. Most aquarium specimens are captive-bred due to habitat threats from logging and mining, with a lifespan of 3–5 years.
Care Requirements
Tank Size:
Minimum 75L for a group of 6–10; 113L or larger preferred for optimal shoaling and swimming space. Base dimensions of at least 90 x 30 cm recommended.
Water Parameters:
- Temperature: 75–82°F (24–28°C); optimal 77–80°F for breeding.
- pH: 6.5–7.8 (slightly acidic to neutral).
- Hardness: 5–15 dGH (soft to moderately hard).
- Ammonia/Nitrite: 0 ppm.
- Nitrate: <30 ppm (ideally <15 ppm, as they are sensitive to nitrates).
- Substrate: Fine sand or gravel; darker substrates enhance neon colouration.
- Décor: Dense live plants (e.g., Java moss, Anubias, Vallisneria) and floating plants for cover and spawning sites. Add driftwood or smooth rocks for hiding, ensuring open swimming areas.
- Filtration: Gentle to moderate flow (4–6x tank volume/hour) using sponge or hang-on-back filters for oxygenation without strong currents.
- Lighting: Moderate to bright to highlight iridescence; floating plants provide shade to reduce stress.
- Other: Tight-fitting lid essential, as they are strong jumpers. Avoid CO2 injection to prevent pH fluctuations.
Maintenance
- Water Changes: 20–30% weekly with dechlorinated water matching tank parameters to maintain stability and low nitrates.
- Tank Cleaning: Siphon uneaten food and debris; lightly vacuum substrate to preserve beneficial bacteria.
- Testing: Weekly checks for pH, hardness, ammonia, nitrite, and nitrate using a reliable test kit to prevent parameter spikes.
- Equipment Check: Ensure filters provide adequate flow and oxygenation, heaters maintain stable temperatures, and lid is secure to prevent escapes.
Diet
- Type: Omnivorous; feeds on small crustaceans, insects, algae, and plant matter in the wild.
- Foods:
- Dry: High-quality flakes or micro-pellets (e.g., Fluval Bug Bites, Hikari Micro Pellets) as a staple.
- Live/Frozen: Brine shrimp, daphnia, bloodworms, cyclops (2–3 times weekly for colour enhancement).
- Plant-Based: Spirulina flakes, blanched vegetables (e.g., spinach, zucchini) for digestive health.
- Feeding: Small portions 2–3 times daily, consumed within 1–2 minutes to prevent overfeeding.
- Notes: Varied diet with live foods enhances neon colours, especially in males. They feed at mid-to-surface levels; ensure food is appropriately sized.
Behaviour and Compatibility
- Temperament: Peaceful but active; males may spar harmlessly during displays, flaring fins to establish dominance.
- Social Behaviour: Shoaling species; keep 6–10 or more (1–2 females per male) to reduce stress and encourage schooling and vibrant displays. Fewer than 6 may lead to shyness or mild aggression.
- Compatible Tankmates:
- Small, peaceful fish: Other rainbowfish (e.g., Melanotaenia maccullochi), neon tetras, rasboras, danios, guppies.
- Bottom-dwellers: Corydoras catfish, kuhli loaches, small gobies (e.g., Pseudomugil gertrudae).
- Incompatible: Aggressive or fin-nipping fish (e.g., tiger barbs, serpae tetras), slow-moving or long-finned fish (e.g., bettas, angelfish), or species requiring soft, acidic water. Avoid mixing with other Melanotaenia species to prevent hybridization.
- Notes: Dense plants and open swimming space reduce skittishness and enhance male displays. Males show best colours in groups with females present.
Breeding Behaviour
Breeding Type: Egg scatterers; spawn daily in small batches, attaching adhesive eggs to plants or spawning mops.
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.
