An energetic and colorful schooling fish from the flowing, shaded streams of Madagascar. Frequently misidentified in the aquarium trade as Bedotia geayi. Unlike Australian rainbowfish, they have an elongated, torpedo-like body. They are incredibly active, thrive in well-oxygenated water with some current, and are peaceful but voracious eaters.
Madagascar Rainbowfish At a Glance
Madagascar Rainbowfish Tank Requirements
Will Madagascar Rainbowfish fit in your tank?
Care guides tell you what Madagascar Rainbowfish needs, the next question is whether your tank can safely provide it. Test Madagascar Rainbowfish against your tank size, maintenance needs, and the fish you already keep before you buy.
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Madagascar Rainbowfish Water Parameters
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Madagascar Rainbowfish Temperament & Compatibility
Madagascar Rainbowfish Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Standard / Unsexed
Typically sold as juveniles before distinct sexual dimorphism appears. Best purchased in a group of 6 or more to allow a natural social hierarchy to form as they mature.
Same care requirements as the base species
Also known as: Juvenile
Male
Noticeably more colorful than females, featuring prominent bold red and black margins on their caudal (tail), dorsal, and anal fins. Males use these vibrant colors to display to females and spar (peacefully) with other males.
Differs in 1 trait from base species
Also known as: Adult Male
Female
Slightly smaller and more subdued in coloration, lacking the intense red and black fin banding seen in males. A mixed-sex school is highly recommended to encourage males to display their best colors.
Differs in 1 trait from base species
Also known as: Adult Female
Madagascar Rainbowfish Care Guide Summary
The Madagascar Rainbowfish, scientifically known as Bedotia madagascariensis, belongs to the Rainbowfish family group. Adults reach a maximum size of approximately 10 cm and have a fusiform body shape with a moderate growth rate. Classified as peaceful, this species primarily occupies the surface and mid-level zones of the aquarium and produces a medium level of biological waste.
To thrive, the Madagascar Rainbowfish requires a freshwater only aquarium with a minimum volume of 150 litres and a tank length of at least 90 cm. Water temperature should be maintained between 22°C and 26°C, with a pH range of 6.5–8.5 and a general hardness of 8–20 dGH. A moderate water flow is preferred.
The Madagascar Rainbowfish is a rewarding species to keep, provided its core environmental needs are met. This species is available in 3 varieties: Standard / Unsexed, Male, and Female. Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.
Madagascar Rainbowfish Habitat Setup
When setting up an aquarium for the Madagascar Rainbowfish, a moderate water flow best suits their natural preferences. Because this species occupies the surface and mid-level zones, the aquarium layout should prioritise adequate surface area with floating cover to make them feel secure near the waterline and open swimming space in the centre of the tank for free movement. Useful additions include driftwood, which can serve as both a hiding place and a dietary supplement. Keepers should note that a tight-fitting lid is essential, as this species is a known jumper.
Madagascar Rainbowfish Compatibility Notes
Classified as peaceful, the Madagascar Rainbowfish is a schooling species that feels most secure in a sizeable group, where natural shoaling behaviour reduces stress and brings out their best colours. When choosing tankmates, shy or slow-feeding tankmates may be outcompeted at feeding time and their energetic swimming style may stress more sedentary or timid species. Selecting tankmates that favour different water layers from the surface and mid-level zones can help reduce competition and territorial overlap.
Madagascar Rainbowfish Recommended Tank Sizes
Standard aquarium sizes that meet the minimum volume and length requirements for Madagascar Rainbowfish.
40 Gallon Breeder
55 Gallon Standard
60 Gallon Breeder
75 Gallon Standard
90 Gallon Standard
125 Gallon Standard
Show 9 more tank sizes
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Frequently Asked Questions About Madagascar Rainbowfish
How big does Madagascar Rainbowfish get?
Madagascar Rainbowfish (Bedotia madagascariensis) typically reaches a maximum adult size of approximately 10 cm. They have a fusiform body shape and a moderate growth rate.
What tank size does Madagascar Rainbowfish need?
A minimum aquarium volume of 150 litres and a tank length of at least 90 cm are recommended for Madagascar Rainbowfish. This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Madagascar Rainbowfish need?
Madagascar Rainbowfish thrives in freshwater only conditions with a temperature range of 22–26°C, a pH between 6.5 and 8.5, and a general hardness of 8–20 dGH. A moderate water flow is preferred.
Is Madagascar Rainbowfish peaceful or aggressive?
Madagascar Rainbowfish is classified as peaceful with an aggression score of 2 out of 10. They are generally well-suited to peaceful community tanks.
How many Madagascar Rainbowfish should be kept together?
Madagascar Rainbowfish is a schooling species and should be kept in groups of at least 6. Larger groups help distribute aggression and encourage natural schooling behaviour.
Does Madagascar Rainbowfish have any special tank requirements?
Yes. Madagascar Rainbowfish benefits from driftwood (digestion/hiding) in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.
Does Madagascar Rainbowfish need a lid on the tank?
Yes. Madagascar Rainbowfish is a known jumper, and a tight-fitting lid or cover is essential to prevent escape. Even a small gap can be enough for a determined fish to leap out.
Top Tank Mates for Madagascar Rainbowfish
These fish are strong compatibility matches for Madagascar Rainbowfish based on water preferences, temperament, adult size, and tank behavior.
Gold Spot Pleco (L001 / L022)
Pterygoplichthys joselimaianus
Ideal Tank MatesMottled Loach
Paracanthocobitis botia
Ideal Tank MatesHillstream Loach
Beaufortia leveretti
Ideal Tank MatesSchwartz's Cory
Corydoras schwartzi
Ideal Tank MatesLeopard Cory
Corydoras leopardus
Ideal Tank MatesGold Laser Cory
Corydoras sp. 'CW010'
Ideal Tank MatesPlants That Suit Madagascar Rainbowfish
These plants pair well with Madagascar Rainbowfish based on shared water preferences, layout fit, and how likely they are to hold up in the same aquarium.
African Onion Plant
Crinum calamistratum
Afzel's Anubias
Anubias afzelii
Amazon Sword
Echinodorus amazonicus
Anacharis
Egeria densa
Anubias Barteri
Anubias barteri
Baby Tears
Lindernia rotundifolia
Fish Similar to Madagascar Rainbowfish
Banded Rainbowfish
Melanotaenia trifasciata
A large, robust, and highly active schooling fish native to Northern Australia. Famous for its intense geographic color variations (such as the red 'Goyder River' morph). They are peaceful but incredibly fast and vigorous swimmers, requiring long aquariums with plenty of open swimming space.
Leggett's Rainbowfish
Glossolepis leggetti
A rare and highly active schooling fish native to the Wapoga and Tiawiwa River systems in West Papua, Indonesia. Known for its distinct sexual dimorphism as it matures, with males developing a deep arch and striking green/blue iridescence. Like most rainbowfish, they require highly oxygenated water, moderate flow, and significant horizontal swimming space.
Blue Rainbowfish
Melanotaenia caerulea
A small, highly active, and colorful schooling fish native to the Kikori River system in Papua New Guinea. They are peaceful but require ample swimming space and a school of their own kind to thrive. Like most rainbowfish, they appreciate well-oxygenated, flowing water and are excellent jumpers. Males develop a striking blue hue with reddish horizontal stripes.
Axelrod's Rainbowfish
Chilatherina axelrodi
A highly active, colorful schooling fish native to Papua New Guinea. Known for a bluish-grey upper body and yellowish-white lower body divided by a dark lateral stripe. Like most rainbowfish, they are incredibly fast, active swimmers that require pristine water, moderate flow, and significant horizontal swimming space.
Parkinson's Rainbowfish
Melanotaenia parkinsoni
A large, incredibly active schooling fish native to Papua New Guinea. They are highly prized for the dramatic, ragged splotches of bright orange or yellow that develop on the males. Like most large rainbowfish, they require highly oxygenated, slightly alkaline water and a long aquarium to accommodate their constant swimming.
New Guinea Rainbowfish
Melanotaenia affinis
An active, schooling species native to the streams of northern New Guinea. Known for their striking lateral stripe and vibrant fin coloration that flashes during morning displays. They are peaceful but highly energetic, requiring ample open swimming space and highly oxygenated water to thrive.