纵带波鱼

Overview

The dark flank stripe and locality-dependent fin colors of Trigonopoma gracile suit a quiet, soft-water group aquarium. Feeding competition deserves attention: very vigorous companions can leave this small fish without enough food.

Distribution & habitat

Its range includes Peninsular Malaysia, Borneo, and Sumatra; the Singapore population may have disappeared. Forest peat-swamp streams and rivers provide acidic blackwater with very little dissolved mineral content. Shade from the canopy and beds of fallen leaves and branches are typical. Some populations occupy clear water with similar chemistry and more extensive aquatic vegetation.

Aquarium setup

Dense planting and a dark substrate enhance its appearance. Soft sand, roots, and branches create sheltered areas, while subdued lighting and floating growth reduce brightness. Leaf litter contributes to a blackwater setting and supports microorganisms that can supplement fry nutrition. Choose plants able to grow under weak light.

Diet & feeding

Small insects, worms, crustaceans, and other zooplankton are likely natural prey. In captivity, quality flakes or fine granules are readily usable alongside regular live or frozen bloodworms, Daphnia, and Artemia.

Behaviour & compatibility

Choose peaceful companions of similar size and compatible water requirements. Avoid boisterous fishes or exceptionally fast feeders. Eight to ten or more individuals help reduce nervousness and produce a more natural group display, with males showing stronger colors during social interactions.

Sexual dimorphism

Mature females have fuller abdomens and often become slightly larger. Males are slimmer and more strongly patterned.

Breeding

Confirmed aquarium breeding information for this species remains uncertain. Procedures used for related egg scatterers can guide an attempt, but should not be treated as a proven species-specific method. These involve mature water, dim lighting, gentle aeration, and fine plants, mops, or mesh to protect eggs. Adults are removed when eggs are seen, and newly swimming fry need very small starter foods.

Notes

Older labels have confused this fish with relatives, particularly through the name Rasbora agilis. Body shape, the dark lateral stripe, and locality information are more useful than a historical commercial name alone.