Leopard Danio Breeding Guide (Danio rerio var. frankei)

Breeding the Leopard Danio, a spotted morph of the Zebra Danio (Danio rerio): sexing, egg-scattering spawning over a marble or mesh base, and rearing the fry.

Overview

The Leopard Danio is a spotted colour morph of the Zebra Danio (Danio rerio); the form previously known as Danio frankei arose from a pigment mutation. Breeding therefore follows the well-documented Zebra Danio method: it is a prolific egg-scattering spawner with no parental care.

Sexing

Sexually mature females are rounder-bellied, slightly less colourful and a little larger than the slimmer males. The difference is clearest at spawning time, when females visibly distend with eggs.

Conditioning

Condition adults as a group on quality dried foods supplemented with small live and frozen items such as bloodworm, Artemia and Daphnia.

Breeding Setup

• Use a dimly lit spawning container half-filled with water.
• Cover the base with mesh, large pebbles or glass marbles so eggs fall out of reach, or use Java moss or grass matting.
• A gentle flow along the tank can be provided by a small filter.
• Temperature toward the upper part of the 18-26 C range, pH 6.0-8.0.

Spawning Behavior & Trigger

Introduced conditioned fish typically spawn the following morning. The species scatters its eggs, releasing 100 or more per spawning, and the eggs fall through the mesh or between marbles. Some breeders use cooler water changes to imitate monsoon rain as a trigger.

Egg & Fry Care

Adults eat any eggs they find, so remove them after about two days and switch to a mature sponge filter to protect the fry. Eggs hatch within roughly 24-36 hours and the young become free-swimming a few days later. Start the fry on Paramecium, infusoria, vinegar eels or a powdered fry food under about 100 microns, moving on to baby brine shrimp and microworm after a couple of weeks.

Common Challenges

The main risks are egg predation by the adults and supplying food fine enough for the very small first-feeding fry.