HomeFreshwater aquarium fishRainbowfish & killifishMurray river rainbowfish Murray river rainbowfish (Melanotaenia fluviatilis) Scientific name: Melanotaenia fluviatilis Castelnau, 1878 The Murray river rainbowfish (Melanotaenia fluviatilis) is a freshwater fish of the family Melanotaeniidae that grows to about 9 cm (3.5 in). It is easy to keep and peaceful, needs carefully chosen tank mates and needs a tank of at least 150 L (40 US gal), water at 18–22°C (64–72°F) and a pH of 6.5–7.2. Native range: Australia, Endemic. Murray river rainbowfish care at a glanceCare levelEasyTemperamentPeacefulCommunity tankWith cautionAdult size9 cm (3.5 in)Minimum tank150 L (40 US gal)Temperature18–22°C (64–72°F)pH6.5–7.2DietOmnivore. Accepts flakes, frozen foods and live foods. BiologyFound in rivers, creeks, drains, ponds and reservoirs. Occurs usually in still or slow-flowing conditions. Inhabits streams, backwaters of larger rivers, drainage ditches, overflow ponds and reservoirs. Usually congregates along grassy banks or around submerged logs and branches. Omnivorous. The most southward-ranging rainbowfish and the only species adapted to low winter temperatures (normally about 10?-15?C). There is evidence that numbers are drastically reduced during winter drought when water temperatures dip below 10?C. Suitable for outdoor pond culture in temperate climates.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameMelanotaenia fluviatilisFamilyMelanotaeniidae (Rainbowfishes, blue eyes)OrderAtheriniformes (Silversides)ClassActinopterygii (Ray-finned fishes)Maximum length11.0Common length8.5EnvironmentFreshwater;; pH range: 7.0 - ?; dH range: 10 - ? benthopelagicClimateTropicalDistributionOceania: endemic to Australia.Conservation status (IUCN)Not EvaluatedThreat to humansHarmlessResilienceMedium, minimum population doubling time 1.4 - 4.4 years (tm=1; tmax=3-4; K=0.17-0.32) More rainbowfish & killifishBanded rainbowfishMelanotaenia trifasciataYellowbelly gudgeonAllomogurnda nesolepisKamaka rainbowfishMelanotaenia kamakaJavanese ricefishOryzias javanicusFlagfishJordanella floridaeBluefin killifishLucania goodeiSee all rainbowfish & killifish Can it live with...?Murray river rainbowfish and Banded rainbowfishMurray river rainbowfish and Blackfin pearlfishMurray river rainbowfish and Dwarf rainbowfishMurray river rainbowfish and Javanese ricefishMurray river rainbowfish and Kamaka rainbowfishMurray river rainbowfish and Lake Kutubu rainbowfishMurray river rainbowfish and Mountain rainbowfishMurray river rainbowfish and Red rainbowfishMurray river rainbowfish and Tami River rainbowfishMurray river rainbowfish and Yellowbelly gudgeon SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0. Aquarium care parameters compiled, checked and converted to metric and imperial units by Guppies.za.net.Last updated 28 September 2026