Golden Wonder Killifish

About

The Golden Wonder Killifish (Aplocheilus lineatus) is one of those species that immediately commands attention the moment you look at the upper third of the tank. Because that's exactly where it lives. Native to Peninsular India and Sri Lanka, this fish turns up across an impressive range of habitats in the wild, from slow hill streams and paddy fields to brackish backwaters and even open wells. That adaptability carries over into the aquarium, where it proves reasonably forgiving once established. The body is slender and torpedo-shaped, built for hugging the surface, and the golden-scaled cultivated form has a warm, almost metallic sheen that sets it apart from plainer wild specimens. Behavior-wise, it's a patient ambush hunter. It hovers just beneath the waterline, watching for anything edible to land above it, and it's more than capable of launching itself clear of the water to grab prey. A tight-fitting lid is non-negotiable. Males can be pushy with each other, so a group needs floating plants and surface cover to break up sightlines and keep the peace. Given their appetite for small tankmates, pair them with fish of comparable size. Unlike many killies, this is not a seasonal species, and with good care it's a rewarding, long-lived surface dweller.