大鳍鱼 · Giant Sword Minnow

Overview

Long pectoral fins, an upturned mouth, a compressed body, and a dark tail-base mark characterize Macrochirichthys macrochirus. Juveniles occasionally enter trade, but eventual size makes this open-water predator unsuitable for most private aquariums.

Distribution & habitat

Its historical Southeast Asian range covers the Mekong region, Thailand, the Malay Peninsula, and major Sunda islands. Several local populations are thought to have disappeared, and Mekong numbers have declined sharply. Pollution, gillnets, and heavy fishing pressure affect the species.

Large lakes and major river channels are typical habitat. Flooded forest and other inundated areas become accessible during the rains.

Aquarium setup

Accommodation is limited to public exhibits or exceptional private installations. Sand, gravel, rocks, and wood may be used, but retain expansive swimming room. Stable clean water, oxygenation, and moderate circulation are essential. Introduce only to a mature system and replace around one-third to one-half of the water weekly.

Fit a secure lid against powerful jumping. Covering the rear and side panels may reduce collisions in this easily startled fish, particularly where space is restrictive.

Diet & feeding

It is strictly carnivorous. Young fish take aquatic and terrestrial invertebrates, while fish prey becomes increasingly important with growth. Small tankmates therefore remain unsafe.

Behaviour & compatibility

A solitary specimen or comparably sized, nonaggressive companions too large to swallow are the better options. Despite its predatory diet, it is easily dominated. A conspecific group is possible only with sufficient room and should start with at least three.

Notes

Mainland and Sundaic populations may eventually prove distinct, but this remains unresolved. Locality information is worth preserving.