A stunning, deep-bodied rainbowfish endemic to Lake Kutubu in Papua New Guinea. Famous for their ability to shift colors from deep teal to bright iridescent blue depending on mood and water quality. They are active schooling fish that thrive in hard, alkaline water.
Turquoise Rainbowfish At a Glance
Turquoise Rainbowfish Tank Requirements
Will Turquoise Rainbowfish fit in your tank?
Care guides tell you what Turquoise Rainbowfish needs, the next question is whether your tank can safely provide it. Test Turquoise Rainbowfish against your tank size, maintenance needs, and the fish you already keep before you buy.
Useful setup supplies
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Turquoise Rainbowfish Water Parameters
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Turquoise Rainbowfish Temperament & Compatibility
Turquoise Rainbowfish Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Standard / Mixed Sex
Commonly sold as juveniles (4-6cm). Coloration may be muted silver/grey until maturity. Must be kept in schools of 6+ to reduce stress.
Differs in 2 traits from base species
Also known as: Juvenile
Male
Mature males develop a very deep chest (nuchal hump) and intense turquoise coloration. They display frequently to females and rival males.
Differs in 3 traits from base species
Also known as: Show Male
Female
More slender and often slightly smaller than males. Color is a more muted bluish-silver. Essential in the school to encourage male coloration.
Differs in 1 trait from base species
Turquoise Rainbowfish Care Guide Summary
The Turquoise Rainbowfish, scientifically known as Melanotaenia lacustris, belongs to the Rainbowfish family group. Adults reach a maximum size of approximately 12 cm and have a compressed 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 Turquoise Rainbowfish requires a freshwater only aquarium with a minimum volume of 160 litres and a tank length of at least 120 cm. Water temperature should be maintained between 20°C and 25°C, with a pH range of 7–9 and a general hardness of 10–25 dGH. A moderate water flow is preferred.
The Turquoise Rainbowfish is a rewarding species to keep, provided its core environmental needs are met. This species is available in 3 varieties: Standard / Mixed Sex, 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.
Turquoise Rainbowfish Habitat Setup
When setting up an aquarium for the Turquoise 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 light plant coverage for partial shade and 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.
Turquoise Rainbowfish Compatibility Notes
Classified as peaceful, the Turquoise 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.
Turquoise Rainbowfish Recommended Tank Sizes
Standard aquarium sizes that meet the minimum volume and length requirements for Turquoise Rainbowfish.
55 Gallon Standard
60 Gallon Breeder
75 Gallon Standard
90 Gallon Standard
125 Gallon Standard
150 Gallon High
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Frequently Asked Questions About Turquoise Rainbowfish
How big does Turquoise Rainbowfish get?
Turquoise Rainbowfish (Melanotaenia lacustris) typically reaches a maximum adult size of approximately 12 cm. They have a compressed body shape and a moderate growth rate.
What tank size does Turquoise Rainbowfish need?
A minimum aquarium volume of 160 litres and a tank length of at least 120 cm are recommended for Turquoise Rainbowfish. This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Turquoise Rainbowfish need?
Turquoise Rainbowfish thrives in freshwater only conditions with a temperature range of 20–25°C, a pH between 7 and 9, and a general hardness of 10–25 dGH. A moderate water flow is preferred.
Is Turquoise Rainbowfish peaceful or aggressive?
Turquoise 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 Turquoise Rainbowfish should be kept together?
Turquoise 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 Turquoise Rainbowfish have any special tank requirements?
Yes. Turquoise Rainbowfish benefits from plants - densely covered and plants - lighly covered in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.
Does Turquoise Rainbowfish need a lid on the tank?
Yes. Turquoise 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 Turquoise Rainbowfish
These fish are strong compatibility matches for Turquoise Rainbowfish based on water preferences, temperament, adult size, and tank behavior.
Pacific Sturgeon
Acipenser transmontanus
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 MatesHi Fin Peppered Cory
Scleromystax macropterus
Ideal Tank MatesPlants That Suit Turquoise Rainbowfish
These plants pair well with Turquoise 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
Anacharis
Egeria densa
Baby Tears
Lindernia rotundifolia
Balansae
Cryptocoryne crispatula
Bonsai Rotala
Rotala indica
Cardinal Plant
Lobelia cardinalis
Fish Similar to Turquoise Rainbowfish
Lake Wanam Rainbowfish
Glossolepis wanamensis
A critically endangered species (IUCN Red List) endemic to Lake Wanam in Papua New Guinea. Known for the extreme deep-bodied shape and metallic green-bronze colors that mature males develop. They are fast, active schooling fish that require hard, alkaline water and plenty of swimming space. Excellent for large planted aquariums.
Kamaka Rainbowfish
Melanotaenia kamaka
Endemic to the karst Lake Kamakawai in West Papua, this is a spectacular and distinctively deep-bodied rainbowfish. As they mature, males develop a robust chest and an intense silvery-blue to purplish sheen. Like all rainbowfish, they are highly active, schooling fish that require spacious tanks with plenty of horizontal swimming room and alkaline, hard water parameters.
Lake Tebera Rainbowfish
Melanotaenia herbertaxelrodi
A striking, highly active schooling fish endemic to Lake Tebera in Papua New Guinea. They feature bright yellow to greenish-blue bodies with a distinct dark lateral stripe. As vigorous swimmers, they require long aquariums and do best in mixed-sex shoals, which encourages males to display their best colors. Due to their highland origin, they prefer slightly cooler, well-oxygenated, and alkaline water.
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.
Lake Mbuta Rainbowfish
Pelangia mbutaensis
A very rare and Critically Endangered rainbowfish endemic to the swampy Lake Mbuta basin in West Papua, Indonesia. It is the sole member of the genus Pelangia. Characterized by a yellowish-tan body grading to silvery-white, they are peaceful, active schooling fish. They are virtually unseen in the standard aquarium trade.
Highlands Rainbowfish
Chilatherina campsi
A rare and elegant species endemic to the central highlands of Papua New Guinea. Unlike many tropical rainbowfish, it thrives in slightly cooler, well-oxygenated water. They are very active, peaceful schooling fish characterized by an olive/mauve back, silvery reflections, and a distinct blackish-to-blue mid-lateral stripe.