Checkered Rainbowfish Breeding Guide

How to breed Melanotaenia splendida inornata, the northern Australian checkered rainbowfish; a pairing plant-spawner laying adhesive eggs that hatch in about a week.

Overview

Melanotaenia splendida inornata, the checkered or chequered rainbowfish, is the northern Australian subspecies of M. splendida, found from the Mary River east to Cape York Peninsula and south to the Jardine River, plus some Torres Strait Islands, according to Wikipedia. As part of M. splendida it is a pairing plant-spawner; the parent species reaches up to about 20 cm standard length per FishBase.

Sexing

Males are the larger, more colourful and deeper-bodied sex, while females are plainer. A male with one or more females makes a suitable spawning group.

Conditioning

M. splendida is omnivorous, taking filamentous algae, aquatic and terrestrial insects, small crustaceans and other invertebrates according to Wikipedia. A varied diet conditions the adults; FishBase notes maturity at roughly 3-4 cm.

Breeding Setup

FishBase lists 20-30 C, pH 6.0-8.0 and hardness 10-30 dH for the species. Spawning is carried out over fine-leaved plants, spawning mops or submerged roots that provide attachment for the adhesive eggs, and breeding takes place year round.

Spawning Behavior & Trigger

According to Wikipedia the male and female form pairs in which the female releases eggs and the male fertilises them; 60-70 golden, round eggs are laid at each spawning and attach to submerged vegetation by an adhesive filament. FishBase cites a total fecundity of around 370 eggs released over a series of spawnings.

Egg & Fry Care

Wikipedia reports that the larvae hatch after around a week, are about 4 mm long with a reduced yolk sac and fully formed mouth and pectoral fins, and start to feed after 24 hours. Egg-laden plants or mops can be moved to a rearing container, and the small fry require very fine first foods such as infusoria before Artemia nauplii.

Common Challenges

The chief difficulty is the very small size of newly hatched fry, which need fine first foods. Removing egg-bearing mops protects the scattered eggs from being eaten by the adults.