Slender rainbowfish (Melanotaenia gracilis)

Scientific name: Melanotaenia gracilis Allen, 1978

The Slender rainbowfish (Melanotaenia gracilis) is a freshwater fish of the family Melanotaeniidae. In the aquarium it needs water at 22–28°C (72–82°F). Native range: Oceania, restricted in the Drysdale and King Edward River systems in the extreme northern portion of Western Australia, 500 km southwest of Darwin.

Slender rainbowfish care at a glance

Temperature: 22–28°C (72–82°F)

Biology

Inhabits large water courses and isolated rocky pools generally bordered with paperbark trees (Melaleuca) which have clear waters and minimal flow during the dry season. Large numbers congregate in shady pools around log snags and submerged branches. Feeds on insects and their larvae, small crustaceans and algae. Sympatric with M. splendida australis. Prefers the following aquarium conditions: pH=7, H=10, 24?C water temperature; is an egg layer and a peaceful community fish.

Source: FishBase, licensed CC BY-NC 4.0.

Species facts

Scientific name: Melanotaenia gracilis
Family: Melanotaeniidae (Rainbowfishes, blue eyes)
Order: Atheriniformes (Silversides)
Class: Actinopterygii (Ray-finned fishes)
Maximum length: 7.5
Environment: Freshwater; benthopelagic
Climate: Tropical
Distribution: Oceania: restricted in the Drysdale and King Edward River systems in the extreme northern portion of Western Australia, 500 km southwest of Darwin.
Conservation status (IUCN): Lower Risk: near threatened (LR/nt)
Threat to humans: Harmless
Uses: Aquarium: potential
Resilience: Medium, minimum population doubling time 1.4 - 4.4 years (Preliminary K or Fecundity.)