Gardneri Killifish Breeding Guide

How to breed Fundulopanchax gardneri, a non-annual plant-spawner: sexing, conditioning, mop or peat spawning, water or dry egg incubation and rearing free-swimming fry.

Overview

Fundulopanchax gardneri is a popular African killifish from tributary streams and marshes of the Benue and Cross River basins of Nigeria and Cameroon. It uses an unusual semi-annual reproductive strategy: eggs are able to withstand a period of drying but will also incubate and hatch when permanently submerged. This makes it one of the most accessible killifish to breed.

Sexing

Males grow larger, are more brightly coloured and develop more-extended fins than females. Males show wavy lines of red spots running along the body with yellow-tinted margins on the dorsal, anal and caudal fins, while females are drab with brown rather than red spots. Maximum length is around 6.5 cm.

Conditioning

Feed adults a varied carnivorous diet to bring them into condition. Suitable breeding water is 20-26 C, pH 6.0-7.5 and hardness 18-179 ppm. Males are territorial, so a single male with one or more females is the usual breeding arrangement.

Breeding Setup

Breeders use either live plants, aquatic mosses or synthetic spawning mops as the egg-deposition medium. Alternatively, some breeders prefer to use a small tray of peat that is removed and dried after spawning. A small air-driven sponge filter keeps the breeding tank gentle.

Spawning Behavior & Trigger

Eggs are deposited continuously among the spawning medium over several days. Eggs are best removed on a daily basis, as the adults will eat any they find. The keeper then chooses between water incubation and dry incubation depending on the medium used.

Egg & Fry Care

Water-incubated eggs normally hatch within 14-21 days depending on temperature. Eggs collected on peat can be dried instead, with 3-4 weeks being the standard drying period before re-wetting triggers hatching. The fry are free-swimming almost immediately and can be offered Artemia nauplii, microworm and similar foods from the start.

Common Challenges

Adults readily eat their own eggs, so daily egg collection is important for good yields. Choosing the wrong incubation regime for the medium, or allowing fungus in standing egg water, are the most common pitfalls.