Eastern Rainbowfish (Melanotaenia splendida) in aquarium
🌿 Freshwater · Tropical

Eastern Rainbowfish

Melanotaenia splendida — Melanotaeniidae
📏 Size: 10–12 cm
Lifespan: 5–8 years
Care level: Beginner

Eastern Rainbowfish Overview

The Eastern Rainbowfish (Melanotaenia splendida) is a freshwater fish belonging to the family Melanotaeniidae. It thrives at temperatures of 22–28 °C with a pH of 7.0–8.5, and requires a minimum tank volume of 150 litres. Known for its peaceful, active community fish, it is considered a beginner-level species. Males display intense colour and fin-spreading to rival males; females are less colourful. Water changes of 25–30 % weekly, stable parameters, and appropriate tank mates are key to long-term success with this species.

Quick fact: Melanotaenia splendida belongs to the family Melanotaeniidae. Care level: beginner.

Eastern Rainbowfish Scientific Classification

RankClassification
FamilyMelanotaeniidae
GenusMelanotaenia
SpeciesMelanotaenia splendida
Water typefreshwater

Eastern Rainbowfish Natural Habitat

Melanotaenia splendida originates from tropical waters. It inhabits freshwater environments and is adapted to the water conditions found in its native range.

Eastern Rainbowfish Appearance & Size

Adults reach 10–12 cm in length. The body is freshwater and the species displays characteristic coloration suited to its environment.

Eastern Rainbowfish Behavior & Temperament

This species is described as a peaceful, active community fish. It naturally schools and should be kept in groups of 6 or more. Activity level is high. Males display intense colour and fin-spreading to rival males; females are less colourful.

TraitValue
Temperamentpeaceful, active community fish
SchoolingYes
Activity levelhigh
Important: Males display intense colour and fin-spreading to rival males; females are less colourful.

Eastern Rainbowfish Water Requirements

ParameterIdeal RangeNotes
Temperature2228°C (7282°F)Use a reliable adjustable heater
pH78.5Avoid sudden swings
Hardness (GH)5–25 dGH dGHSoft to moderately hard
Ammonia0 ppmAny detectable ammonia signals a problem
Nitrite0 ppmToxic even at low levels
Nitrate<20 ppmManage through regular partial water changes
Min. tank150L (40 gal)Larger tanks are easier to keep stable
Important: Always dechlorinate tap water before adding it to the tank. Chlorine and chloramines damage a fish's gills and reduce life expectancy.

Interesting Facts About Eastern Rainbowfish

  • Eastern Rainbowfish colour varies greatly by locale; fish from different rivers may look like separate species.
  • Active surface swimmer and jumper — a tight-fitting lid is essential.
  • Native to eastern Australia and parts of New Guinea.

Related Species & Guides

Editorial review

This species profile was reviewed for biological accuracy and practical aquarium care guidance. For suspected illness or disease, test your water parameters first and consult an aquatic veterinarian if symptoms persist.