Species description

Care, breeding and tankmates

Fish profile

Temperament

Semi-aggressive

The Lyretail Killifish is a peaceful, shy, and relatively quiet species that does best in peaceful surroundings. Males can exhibit territorial behavior towards each other, though serious injuries are rare if the tank provides enough visual boundaries. They will not bother other species but can be easily intimidated by active or aggressive tankmates.

Diet

Omnivore

In the wild, these fish are carnivores that feed primarily on small insects, insect larvae, and aquatic crustaceans. In the aquarium, they thrive on live or frozen foods such as daphnia, brine shrimp, and bloodworms. While tank-bred specimens will accept high-quality dry flakes or granules, their colors and breeding success are greatly enhanced by fresh foods.

Life expectancy

2-3 years

Unlike annual killifish, the Cape Lopez Lyretail is a non-annual species with a lifespan of 2 to 3 years in captivity under optimal care. In some cases, well-conditioned specimens have been known to live for more than 3 years. Maintaining stable, clean water parameters and a high-quality diet are key factors in maximizing their longevity.

Adult size

6 cm

Sex ratio

Harem

For best results, these fish should be stocked in pairs or trios consisting of one male and two females. Keeping them in a harem helps distribute the male's breeding behavior and prevents any single female from becoming exhausted. In larger, heavily planted aquariums, multiple males can be kept together, provided there are enough females and visual barriers to limit aggression.

Feeding frequency

Twice daily

Adult Lyretail Killifish should be fed once or twice daily with portion sizes they can consume within a few minutes. Overfeeding must be avoided as uneaten food will quickly foul their water. Spawning pairs or conditioning fish can be fed twice daily with high-protein live foods to encourage egg production.

Bioload

Low

The Lyretail Killifish has a very low biological footprint due to its small adult size and slow metabolism. A standard sponge filter or gentle internal filter is highly sufficient to process their waste without creating excessive water turbulence. Regular weekly water changes of 10% to 15% are recommended to keep nitrate levels low and prevent the accumulation of organic compounds.

Flow

Stagnant

This species inhabits slow-moving streams and swamps, meaning they have a strong preference for weak water flow. Strong currents cause stress and exhaust these fish, as they are not adapted to swimming against fast-moving water. A simple sponge filter or an adjustable filter set to a low flow rate is ideal to keep the environment calm.

Jump risk

Yes

These killifish are exceptional jumpers and can easily escape through even the smallest openings in the lid. In their natural habitat, jumping is an adaptation used to traverse land or escape predators. Therefore, a tightly fitting cover glass or canopy is absolutely mandatory to prevent tragic losses.

Reproduction

Oviparous

Breeding this species is relatively easy and highly rewarding for hobbyists. They are egg-hangers that deposit their eggs on spawning mops, fine-leaved plants like Java moss, or peat moss. The eggs incubate for 10 to 20 days depending on the temperature, and the fry are large enough to accept newly hatched brine shrimp immediately.

Compatibility & tankmates

Aphyosemion australe is best suited for dedicated single-species tanks or peaceful community aquariums. Ideal tankmates include small, peaceful fish such as dwarf corydoras, small tetras, rasboras, and dwarf cichlids. Active, nippy, or aggressive fish should be avoided as they will easily outcompete and stress this shy killifish.

Tank level

Top/Middle

Aphyosemion australe is a benthopelagic species that primarily occupies the middle to upper levels of the water column. They are particularly drawn to areas with dense vegetation, root networks, and floating plants where they feel secure. While they may occasionally venture to the bottom to forage, they spend most of their time hovering near the surface or mid-water layers.