Pearl Danio (Danio albolineatus)

Danio albolineatus is native to Myanmar, Thailand, and the island of Sumatra, where it inhabits a diverse range of freshwater environments — from slow-moving lowland rivers and ponds to faster-flowing hill streams. It is named 'albolineatus' (white-lined) for the horizontal pale stripe visible under certain lighting along the lateral line.

The most striking feature of Pearl Danios is not a single bold color but a diffuse, shifting iridescence: the body shimmers with overlapping pink, salmon, gold, blue-green, and violet highlights that change as the fish moves and as light angles change. Under aquarium lighting, schools of Pearl Danios create a soft, sparkling visual effect that belies their relatively modest individual coloration. Females are slightly larger and rounder; males are slimmer and sometimes more vibrantly iridescent.

Reaching 6–7 cm, Pearl Danios are slightly larger than Zebra Danios but share the same active, energetic schooling behavior and environmental adaptability. They are robust fish that tolerate a range of water conditions and are suitable for beginner and experienced aquarists alike.

In the aquarium, Pearl Danios display best in schools of 10 or more against a dark background, where the collective pearlescent shimmering of the group creates an impressive, ever-changing light display.

Pearl Danios are highly adaptable: pH 6.5–7.5, hardness 5–15 dGH, and temperatures 18–26°C. They tolerate a range of water conditions including slightly cooler temperatures, making them suitable for unheated indoor aquariums in temperate climates.

A minimum 80-liter aquarium with significant horizontal swimming space suits a group of 8–10 well. Provide moderate current, good oxygenation, and dense plantings around the perimeter with open central swimming space. A tight lid is important — they are active jumpers.

Feed quality flake food, micro pellets, and live or frozen supplements: daphnia, baby brine shrimp, bloodworms, and micro worms. They are enthusiastic, competitive feeders that accept most aquarium foods readily.

Pearl Danios are entirely peaceful and compatible with virtually all community species: tetras, rasboras, barbs, corydoras, small catfish, and peaceful loaches. Avoid very slow-moving, long-finned species that may be stressed by their boisterous swimming.

Keep in groups of 8–10 or more for natural schooling behavior. The pearlescent iridescence is best appreciated in larger groups against dark backgrounds. Weekly water changes of 25–30% maintain water quality.