Fireline Danio Care Guide - Aquarium Setup, Diet & Breeding

The Fireline Danio is a small, lively Devario recognised for its slender body and vivid red-orange line running along the flanks. This warm colour contrasts with darker blue, greenish or metallic markings, producing an especially attractive appearance when the fish are displaying or moving through the aquarium together.

Like other danios, it is an active midwater swimmer that spends much of its time exploring open areas and interacting with members of its own group. Fireline Danios are generally peaceful, but their energetic movements are best appreciated in a proper shoal rather than as isolated individuals.

In nature, this species is associated with clear hill streams and smaller tributaries, where flowing water passes over gravel, pebbles and rock. The fish use sheltered edges, plants and submerged structure for cover while feeding among the current.

Devario sondhii remains less commonly seen than several better-known danios, which gives it particular appeal to aquarists interested in unusual Southeast Asian cyprinids. Its compact size, striking lateral stripe and busy behaviour make it a distinctive feature in a peaceful freshwater community.

Fireline Danios are native to northern Myanmar in Southeast Asia, particularly clear, fast-flowing streams associated with the Salween River drainage. They come from shallow waters with abundant vegetation, stones and woody debris.

A group of Fireline Danios should have at least 60 litres of water, with a footprint of roughly 60 by 30 cm to provide meaningful swimming space. Use a secure lid because active danios may jump, and provide open water at the front and centre of the aquarium alongside dense plants, driftwood and smooth stones around the edges. A fine gravel or sand substrate is suitable, while gentle-to-moderate water movement helps recreate their stream habitat without making the fish struggle continuously.

Up to 5 cm (2 inches). Females are usually slightly larger and deeper-bodied than males.

Fireline Danios are omnivores and should receive a varied diet of quality small flakes, micro pellets and granules. Supplement these staples with live or frozen foods such as baby brine shrimp, daphnia, cyclops and finely chopped bloodworm. Their small mouths benefit from several modest feedings, and occasional vegetable-based foods can add useful variety.

Fireline Danios are peaceful community fish and can be kept with similarly sized, non-aggressive species that enjoy comparable water conditions. Suitable companions include small rasboras, peaceful tetras, other mild danios, small Corydoras, kuhli loaches, hillstream loaches and gentle dwarf cichlids. Avoid slow-moving or long-finned fish that may be unsettled by their constant activity, as well as large, predatory or aggressive species that could view them as prey.

Fireline Danios are egg-scattering spawners that can breed in a mature, well-conditioned aquarium. Feed a group generously with live or frozen foods, then place several males and females in a separate shallow breeding tank with fine-leaved plants, spawning mops or a protective mesh over the base. The adults should be removed after spawning because they may eat the eggs. Eggs typically hatch within a few days, and the tiny fry can be raised on infusoria or a specialist liquid fry food before moving on to newly hatched brine shrimp.

Males are generally slimmer and show stronger colour contrast, particularly when displaying. Females tend to have a fuller abdomen, especially when carrying eggs, and may appear slightly larger overall.