The Sepik Rainbowfish, also known as the Rosy Rainbowfish, is a vibrant schooling fish native to the floodplains, swampy lagoons, and slow-moving rivers of New Guinea. They are highly active swimmers that display stunning metallic and red coloration. They thrive in densely planted aquariums with ample open swimming space and require a group to feel secure and display their best colors.
Sepik Rainbowfish At a Glance
Sepik Rainbowfish Tank Requirements
Will Sepik Rainbowfish fit in your tank?
Care guides tell you what Sepik Rainbowfish needs, the next question is whether your tank can safely provide it. Test Sepik Rainbowfish against your tank size, maintenance needs, and the fish you already keep before you buy.
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Sepik Rainbowfish Water Parameters
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Sepik Rainbowfish Temperament & Compatibility
Sepik Rainbowfish Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Male
Males are larger and become significantly deeper-bodied as they age. They display intense reddish-orange coloration with shimmering scales to attract females. Best kept with multiple females to disperse chasing behavior.
Differs in 1 trait from base species
Also known as: Male Rosy Rainbowfish, Red Dragon
Female
Females are smaller (typically up to 10cm), shallower-bodied, and exhibit more subdued, silvery-greenish coloration compared to males. A ratio of 2-3 females per male is recommended in the aquarium.
Differs in 1 trait from base species
Also known as: Female Sepik Rainbowfish
Sepik Rainbowfish Care Guide Summary
The Sepik Rainbowfish, scientifically known as Glossolepis multisquamata, belongs to the Rainbowfish family group. Adults reach a maximum size of approximately 12 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 Sepik Rainbowfish requires a freshwater only aquarium with a minimum volume of 110 litres and a tank length of at least 90 cm. Water temperature should be maintained between 24°C and 29°C, with a pH range of 6.2–7.5 and a general hardness of 4–12 dGH. A moderate water flow is preferred.
The Sepik Rainbowfish is a rewarding species to keep, provided its core environmental needs are met. This species is available in 2 varieties: 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.
Sepik Rainbowfish Habitat Setup
When setting up an aquarium for the Sepik 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 dense planting to provide cover, break sightlines, and reduce stress. Keepers should note that a tight-fitting lid is essential, as this species is a known jumper.
Sepik Rainbowfish Compatibility Notes
Classified as peaceful, the Sepik Rainbowfish is a social species that requires the company of its own kind to thrive. When choosing tankmates, 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.
Sepik Rainbowfish Recommended Tank Sizes
Standard aquarium sizes that meet the minimum volume and length requirements for Sepik Rainbowfish.
30 Gallon Breeder
40 Gallon Breeder
55 Gallon Standard
60 Gallon Breeder
75 Gallon Standard
90 Gallon Standard
Show 10 more tank sizes
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Frequently Asked Questions About Sepik Rainbowfish
How big does Sepik Rainbowfish get?
Sepik Rainbowfish (Glossolepis multisquamata) typically reaches a maximum adult size of approximately 12 cm. They have a fusiform body shape and a moderate growth rate.
What tank size does Sepik Rainbowfish need?
A minimum aquarium volume of 110 litres and a tank length of at least 90 cm are recommended for Sepik Rainbowfish. This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Sepik Rainbowfish need?
Sepik Rainbowfish thrives in freshwater only conditions with a temperature range of 24–29°C, a pH between 6.2 and 7.5, and a general hardness of 4–12 dGH. A moderate water flow is preferred.
Is Sepik Rainbowfish peaceful or aggressive?
Sepik Rainbowfish is classified as peaceful with an aggression score of 2 out of 10. They are generally well-suited to peaceful community tanks.
Can Sepik Rainbowfish live alone?
No, Sepik Rainbowfish should be kept in groups of at least 5 to reduce stress and encourage natural behaviour.
Does Sepik Rainbowfish have any special tank requirements?
Yes. Sepik Rainbowfish benefits from plants - densely covered in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.
Does Sepik Rainbowfish need a lid on the tank?
Yes. Sepik 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 Sepik Rainbowfish
These fish are strong compatibility matches for Sepik Rainbowfish based on water preferences, temperament, adult size, and tank behavior.
Mottled Loach
Paracanthocobitis botia
Ideal Tank MatesSchwartz's Cory
Corydoras schwartzi
Ideal Tank MatesLeopard Cory
Corydoras leopardus
Ideal Tank MatesGold Laser Cory
Corydoras sp. 'CW010'
Ideal Tank MatesDainty Cory (Salt and Pepper Cory)
Corydoras habrosus
Ideal Tank MatesZebra Shovelnose (Tigrinus Catfish)
Brachyplatystoma tigrinum
Ideal Tank MatesPlants That Suit Sepik Rainbowfish
These plants pair well with Sepik Rainbowfish based on shared water preferences, layout fit, and how likely they are to hold up in the same aquarium.
Afzel's Anubias
Anubias afzelii
Amazon Sword
Echinodorus amazonicus
Anacharis
Egeria densa
Anubias Barteri
Anubias barteri
Baby Tears
Lindernia rotundifolia
Balansae
Cryptocoryne crispatula
Fish Similar to Sepik Rainbowfish
Mamberamo Rainbowfish
Melanotaenia mamberamo
Commonly known in the trade as the Red Dragon or Sepik Rainbowfish (widely recognized scientifically as Glossolepis multisquamata). Native to the floodplains and swampy lagoons of the Mamberamo river basin in New Guinea. This stunning, highly active schooling fish brings brilliant metallic colors to the aquarium. Unlike many rainbowfish that need hard/alkaline water, this species thrives in slightly acidic to neutral environments. They are peaceful but require long tanks to accommodate their energetic swimming habits.
Red Rainbowfish
Glossolepis incisus
Native to Lake Sentani in Indonesia, this species is famous for the brilliant salmon-red coloration of mature males. They are large, active schooling fish that develop a distinct high-arched back as they age. Females are vastly different in appearance (olive-gold). They require hard, alkaline water and plenty of swimming space.
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.
Bulolo Rainbowfish
Chilatherina bulolo
A rare and highly active rainbowfish native to the fast-flowing mountain streams and white-water rapids of the Markham and Ramu river systems in Papua New Guinea. They possess a silvery body with a distinct black streak on the upper and lower edges of the caudal fin. Because of their specialized natural habitat, they require highly oxygenated, fast-flowing water and alkaline conditions to thrive in an aquarium.
Mubi Rainbowfish
Melanotaenia mubiensis
A rare, energetic, and colorful schooling fish native to the clear, limestone-filtered streams of the Kikori River system in Papua New Guinea. As they mature, males develop striking colors and deep bodies. Like most rainbowfish, they are highly active, requiring long aquariums with moderate flow and moderately hard, alkaline water to thrive.
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.