Guenther's Nothobranchius

Nothobranchius guentheri is one of the most widely kept annual killifish in the hobby, hailing from temporary pools on Zanzibar Island and the adjacent Tanzanian coast. Males are stunning — their body scales range from deep orange to red, each edged with an iridescent blue border that creates a mosaic effect intensifying during spawning displays. Females are plain brown but essential to a functional breeding group.

This species is slightly larger than many of its relatives and benefits from a dedicated 40 L species tank with peat substrate and low lighting. Water should be soft and slightly acidic. Males are aggressive toward one another, so a single-male harem setup works best. Eggs require a dry incubation period of 8–12 weeks before re-wetting triggers hatching.

N. guentheri is considered an excellent first annual killifish due to its relative hardiness and availability. Its spectacular colouration and fascinating life history make it a perennial favourite at killifish society auctions worldwide.

Water: 20–26 °C, pH 6.0–7.5, soft to moderately hard (GH 2–10). Tank: 40 L species tank with peat substrate; ensure tight-fitting lid as it is a jumper. Feeding: Live or frozen Daphnia, Artemia nauplii, bloodworm, and tubifex; feed once or twice daily. Breeding: Collect eggs from peat substrate and store dry for 8–12 weeks before re-wetting. Compatibility: Best kept as a species; avoid mixing males; females can be kept together.