Phoenix Rasbora Care Guide - Aquarium Setup, Feeding & Breeding

The Phoenix Rasbora is a tiny, jewel-like schooling fish with a warm reddish-orange body, a darker horizontal marking and translucent fins. Its compact size and subtle coloration make it especially appealing in planted nano aquariums, where a group can look like a shifting cloud of embers.

This species is peaceful and active without being boisterous. Phoenix Rasboras spend much of their time in the middle and upper levels of the aquarium, displaying more confidence and natural social behaviour when kept in a proper group. Males may show richer colour and briefly spar with one another without usually causing harm.

In the wild, Boraras merah is associated with shallow, slow-flowing blackwater habitats beneath dense tropical vegetation. Fallen leaves, submerged roots and suspended tannins create a dim, complex environment, while the water is typically soft, acidic and low in mineral content.

Like other Boraras, the Phoenix Rasbora is closely related to the small rasboras of Southeast Asia and is prized for combining a miniature adult size with lively schooling behaviour. Its small mouth and delicate build mean it is best viewed as a specialist nano-community fish rather than a companion for large or vigorous species.

Phoenix Rasboras are native to Indonesian Borneo, particularly the island’s Kalimantan region. They inhabit slow-moving blackwater streams, peat swamps and forest pools rich in tannins and leaf litter.

A group of Phoenix Rasboras should be kept in an aquarium of at least 40 litres, with a footprint around 60 × 30 cm or larger. Use gentle filtration and subdued lighting, with dense fine-leaved plants, moss, floating cover, branches and dried leaves to provide security and mimic their forest-stream habitat. A dark sand or fine-gravel substrate complements their colour and allows leaf litter and natural tannins to be used safely. Leave some open water for schooling, while avoiding strong currents and abrupt environmental changes.

Up to about 2 cm (0.8 in) in total length. Females are usually slightly larger and deeper-bodied than males.

Feed Phoenix Rasboras a varied diet of finely powdered or suitably tiny quality flakes, nano granules, baby brine shrimp, daphnia, cyclops and other small frozen or live foods. Their mouths are very small, so food should be offered in miniature portions that they can swallow easily. Regular live or frozen foods help maintain their colour and condition, while small, frequent feedings reduce waste and ensure that timid individuals get enough to eat.

Phoenix Rasboras are excellent companions for other peaceful, similarly sized nano fish. Suitable tankmates include chili rasboras, other gentle Boraras species, small pencilfish, celestial pearl danios, Otocinclus and small freshwater shrimp, provided the aquarium is appropriately arranged. Avoid angelfish, gouramis, larger rasboras, barbs, cichlids, predatory catfish and other boisterous fish that may eat them, intimidate them or outcompete them for food.

Phoenix Rasboras are continuous egg scatterers that may spawn among fine-leaved plants, moss and leaf litter. For more reliable results, condition a group with small live or frozen foods and place them in a mature, densely planted breeding tank with gentle filtration. The adults should be removed or separated from the eggs, as they may eat them. The eggs usually hatch within a few days, and the tiny fry initially need infusoria or another appropriately microscopic first food before progressing to newly hatched brine shrimp.

Males are generally slimmer and more intensely coloured, especially when displaying, with stronger reddish tones. Females tend to be larger, rounder through the abdomen and somewhat less vividly marked.