Lake Kurumoi Rainbowfish Breeding Guide

How to breed Melanotaenia parva, a Critically Endangered rainbowfish from Lake Kurumoi, West Papua; a pairing plant-spawner laying adhesive eggs on fine vegetation.

Overview

Melanotaenia parva is a rainbowfish endemic to Lake Kurumoi in the Yakati River watershed of West Papua, Indonesia, sitting at around 400 m elevation in a lake without visible natural drainage according to FishBase. It reaches about 6.7 cm standard length. FishBase lists it as Critically Endangered on the IUCN Red List (assessed 2019), which makes captive breeding particularly valuable.

Sexing

As in other Melanotaenia, males are the larger and more intensely coloured sex, deepening in body and colour with maturity, while females remain plainer. A male can be set up with one or more females for spawning.

Conditioning

FishBase records a trophic level of about 2.9, consistent with an omnivorous diet. Conditioning the adults on a varied diet of small live, frozen and prepared foods readies them for spawning.

Breeding Setup

FishBase notes distinct pairing during reproduction for this species. Like other rainbowfish it spawns over fine-leaved plants or spawning mops that provide attachment for the adhesive eggs. The consulted source does not give specific captive temperature or pH figures, which are therefore omitted.

Spawning Behavior & Trigger

FishBase describes the species as forming distinct pairs during reproduction. In the genus the female releases adhesive eggs that attach to plants over a period, rather than scattering all eggs at once; eggs released over successive days are typical of Melanotaenia rainbowfish.

Egg & Fry Care

The adhesive eggs hang on the spawning medium and can be moved to a separate container to protect them. Newly hatched rainbowfish fry are very small and need fine first foods such as infusoria or commercial fry food before Artemia nauplii. Specific incubation and fry data for this species are not given in the consulted source and are therefore omitted.

Common Challenges

Because the species is Critically Endangered with a single tiny natural range, maintaining a genetically diverse captive population is important. The usual rainbowfish bottleneck of tiny first-feeding fry applies, requiring very small live or prepared foods.