Melanotaenia praecox
All the colour of a full-size rainbow in a nano-friendly package: iridescent blue body, neon-red fins. Side-lighting from the front of the hood makes the blue absolutely pop. Schools tightly and tolerates a wider parameter range than its bigger Melanotaenia cousins.
Dwarf Neon Rainbowfish (Melanotaenia praecox) reaches 5–6 cm as an adult and needs a minimum tank of 75 L. Native to Mamberamo River basin, West Papua, it lives in the mid to top water column with a peaceful temperament. Aim for 22–28 °C, pH 6.5–7.5, and 5–15 dGH hardness. Lifespan is 3–5 years with good care. Keep dwarf neon rainbowfish in groups of 6+, yes schoolers need numbers to display natural behaviour. Diet: omnivore, Micro pellets, flake, frozen daphnia and bloodworms. Small upturned mouth, keep food fine. Plant-safe: Yes. Shrimp-safe: Mostly (may eat shrimplets).
Care at a glance
All the colour of a full-size rainbow in a nano-friendly package: iridescent blue body, neon-red fins. Side-lighting from the front of the hood makes the blue absolutely pop. Schools tightly and tolerates a wider parameter range than its bigger Melanotaenia cousins.
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The parameters that decide whether dwarf neon rainbowfish fits in your tank.
Mid to Top
Yes
Group of 6+
Melanotaeniidae
Omnivore
Micro pellets, flake, frozen daphnia and bloodworms. Small upturned mouth, keep food fine.
3–5 yrs
Medium
Mamberamo River basin, West Papua
Mamberamo River basin, West Papua
Tank-mate safety and the species this one is documented to thrive (or fail) alongside.
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Dwarf Neon Rainbowfish (Melanotaenia praecox) needs a minimum tank of 75 L. They live in the mid to top water column and should be kept in groups of 6+, so a longer footprint matters more than depth.
Target 22–28 °C, pH 6.5–7.5, and 5–15 dGH hardness. Acclimate slowly when moving them between water sources.
Shrimp safety: Mostly (may eat shrimplets). Plant safety: Yes.
Dwarf Neon Rainbowfish are omnivore. Micro pellets, flake, frozen daphnia and bloodworms. Small upturned mouth, keep food fine.
On Fin & Stem's 1–5 difficulty scale this species rates 2/5. Forgiving, beginner-friendly once the tank is cycled. Breeding difficulty: medium.
Typical lifespan in a well-maintained tank is 3–5 years.
A planted tank is a system. Pair this fish with one entry from each other pillar to plan the whole scape.
