Not furry, but we like them anyway.

Phoenix Rasbora

Boraras merah

Also called Rasbora merah

SpeciesShort profile

From Southern and western Borneo (Central Kalimantan), Indonesia; peat-rich blackwater streams1 2 3

At a glance the quick version

Length1.5 to 2 cm3 1 2

Sizetiny

Standard length

Peaceful

Rich red colouring

Excellent for planted nano tanks

Looks how to spot one

Miniature, slender scaled cyprinid

A tiny, slim rasbora of about 1.5-2 cm. Its body is reddish, with the red concentrated around darker blotches and markings on the flanks rather than spread evenly as in its close relatives. Males are the more vivid sex, females are rounder and often a little larger.1 3

Coloursredorange-reddark flank markings1 3

Personality what they are like

Very peaceful but timid. It does best alongside other small, quiet species and becomes bolder in a group.1

Daily activity how busy a day looks

A gentle, low-energy swimmer that likes plant cover and calm water.1

Grooming and care the hands-on bits

Needs soft, acidic, clean water with stable conditions; regular small water changes and a varied diet keep it colourful.1

Home where they are happiest

A minimum footprint of about 45 x 30 cm for a group. Temperature 20-28 °C, pH 4.0-6.5, hardness 1-5 dGH. Dense planting, leaf litter and low flow suit it well.1

Food basics what goes in the bowl

Probably a micropredator in nature. Offer small live and frozen foods such as Daphnia and Artemia together with good quality dried foods.1

Company who they like around

A schooling species; keep at least 8-10 together. Good partners are other tiny peaceful fish, shy Betta species and dwarf shrimp.1

The story where it all began

Maurice Kottelat described this fish in 1991 as Rasbora merah, from specimens collected in the Jelai Bila river basin in Central Kalimantan. It was moved into the newly created genus Boraras in 1993.1 3 2

Fun facts for the dinner table

1
'Merah' is the Indonesian word for red, chosen for the fish's body colour.3
2
The genus name Boraras is an anagram of Rasbora.3
3
It shares its peat swamp homeland in Borneo with its close relative the chili rasbora.4
4
It scatters eggs a few at a time over a long period rather than spawning in one go.1

Recognised by the official bits

IUCN Red List: Assessed as Data Deficient (February 2019)2
FishBase: Described by Kottelat in 19912

The care rhythm Furry Diary remembers it for you

A typical home-care rhythm for a Phoenix Rasbora. It is our own starting plan, not a vet's advice, and you can change every line in the app.

FeedingSmall amounts once or twice a dayevery day
Temperature checkevery day
Water changeAbout 25% of the waterevery week
Water testevery week
Glass cleanevery week
Filter rinseRinse in old tank water, never tap waterevery month

Start a free diary

Chili Rasbora

Strawberry Rasbora

Dwarf Rasbora

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Where this comes from

Every breed page shows where each fact comes from. If we got something wrong, sorry, we are pet people, not a science magazine. Tell us at [email protected] and we will fix it.

Seriously Fish - Boraras merah seriouslyfish.comused for origin, size, water parameters, care, diet, behaviour, history
FishBase - Boraras merah fishbase.seused for author/year, IUCN status, size, distribution
Wikipedia - Boraras merah en.wikipedia.orgused for etymology, size, colour, genus anagram fact
Wikipedia (de) - Moskitobärbling de.wikipedia.orgused for shared habitat fact

Checked 2026-09-30. Text is written in our own words from these sources.