Phoenix Rasbora (Boraras merah) Care Guide
A tiny jewel of a fish from Borneo's blackwater streams with a deep red body marked by a bold dark lateral stripe and spot. Males develop intense crimson coloration when in breeding condition.
Compiled by Aquairi from published sources · Published · Updated
Overview
Boraras merah is a species in the family Cyprinidae. A tiny jewel of a fish from Borneo's blackwater streams with a deep red body marked by a bold dark lateral stripe and spot. Males develop intense crimson coloration when in breeding condition. Excellent for nano planted tanks, it does best in large schools in soft, tannin-stained water with leaf litter.
Taxonomy
- Family: Cyprinidae
- Genus: Boraras
- Scientific name: Boraras merah
- Other names: Merah Rasbora, Boraras merah
- Origin: Southeast Asia
Habitat
Endemic to peat swamps of southern Borneo, Indonesia. Inhabits very soft, acidic, tannin-stained blackwater shaded by forest canopy. A tiny shoaling Boraras species with red body markings; sensitive to water quality and best kept in dedicated soft-water setups.
Tank requirements
- Minimum tank volume: 20 L
- Temperature: 22-27 °C
- pH: 4-6.5
- GH: 1-6 °dGH
- Water flow: low
- Adult size: 1.5-2 cm
- Lifespan: 2-4 years
- Recommended group size: ≥ 10
- Difficulty: beginner
Diet
Classified as omnivore. Recommended feeding frequency: 2x daily. In captivity, offer a varied diet appropriate to the species — quality prepared foods supplemented with frozen or live items of suitable size.
Compatibility
- Temperament: peaceful
- Swimming level: middle
- Compatible tank mates: Chili Rasbora, Exclamation Point Rasbora, Pygmy Corydoras, Cherry Shrimp, Otocinclus
- Avoid with: Any fish large enough to eat them, Aggressive species
Breeding
- Breeding strategy: egg-scatterer
- Breeding difficulty: intermediate
Phoenix Rasbora (Boraras merah) Breeding Guide
Overview
Boraras merah is an egg-scattering, continuous spawner that exhibits zero parental care. In a well-established aquarium fry may appear naturally without intervention; a small dedicated container is used when higher numbers of fry are wanted.
Sexing
Mature females are noticeably rounder-bodied and often a little larger than males. Males display superior coloration, with dominant individuals showing the most intense hues.
Conditioning
Condition adults well, then introduce two to three well-conditioned pairs to the spawning container, transferring them slowly to minimise stress. If conditions are to their liking they should begin to spawn the following morning.
Breeding Setup
Use a small 10-15 litre container with minimal lighting and a bare substrate or mesh that lets eggs fall through but prevents adult access; plastic grass matting also works. Add a dense clump of java moss or fine-leaved plants filling about half the space, plus a small air-powered sponge filter. Spawning water is pH 5.0-6.5, hardness 1-5 °H, with temperature toward the upper end of the normal range (around 28 °C).
Spawning Behavior & Trigger
The species scatters its eggs continuously among the moss and plants. To prevent the adults from consuming the eggs, remove them after no more than two days in the spawning container.
Egg & Fry Care
Eggs hatch by day two, after which the fry survive on their yolk sacs for about 24 hours. They require microscopic foods such as Paramecium initially; after 7-10 days they accept Artemia (brine shrimp) nauplii and microworms. Delay water changes for one to two weeks to avoid shocking the young fish.
Common Challenges
As with other Boraras, the key difficulties are first foods small enough for the minute fry and avoiding losses from early water changes. Soft, acidic water and prompt removal of adults support a successful spawn.