Hypseleotris Sp. Firetail Gudgeon

The Firetail Gudgeon is an undescribed or informally named member of the Hypseleotris genus native to stream and river systems in eastern or northern Australia, characterised primarily by the vivid red to orange-red caudal fin in breeding males — a feature that gives the fish its common name. The body is otherwise a warm brown to olive-gold with iridescent scale highlights, and males develop stronger colour overall during breeding condition. Females are plainer and more compact. Like the closely related Empire Gudgeon, the Firetail is an amphidromous species that inhabits a range of stream and river habitats. In the aquarium it is a hardy, relatively undemanding fish that accepts most foods and coexists peacefully with similarly sized species. It is a good choice for an Australian native fish display or a subtropical community tank and tolerates a wide temperature range without heating during cooler months.

Water: 18–28 °C, pH 6.8–7.8, GH 5–18, KH 3–12; adaptable; can be kept unheated in temperate climates in summer. Tank: 80 L minimum; mixed sand and gravel substrate; driftwood, rocks, and plants; moderate flow. Feeding: Omnivore; frozen bloodworm, daphnia, brine shrimp, small pellets, and occasional flake food. Breeding: Amphidromous; eggs scattered on substrate or plants; male may guard briefly; larvae difficult to raise. Compatibility: Peaceful; excellent with Australian rainbowfish, small tetras, and other peaceful gudgeons.