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.
At a Glance
Tank Requirements
Water Parameters
Temperament & Compatibility
Available Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Male (Standard)
The desirable bright red form. Males develop a tall body height (high back) and intense red color as they mature. They are boisterous and will spar with other males to display dominance.
Differs in 2 traits from base species
Also known as: Super Red, High Back
Female
Drastically different from males. Females are olive-green/yellowish with silvery scales and maintain a more streamlined shape. Essential in the tank to encourage males to display their best colors.
Differs in 3 traits from base species
Also known as: Olive, Silver
Red Rainbowfish Care Summary
The Red Rainbowfish, scientifically known as Glossolepis incisus, belongs to the Rainbowfish family group. Adults reach a maximum size of approximately 15 cm and have a compressed body shape with a moderate growth rate. Classified as mostly peaceful, this species primarily occupies the mid-level and surface zones of the aquarium and produces a medium level of biological waste.
To thrive, the Red Rainbowfish requires a freshwater only aquarium with a minimum volume of 200 litres and a tank length of at least 120 cm. Water temperature should be maintained between 22°C and 28°C, with a pH range of 7–8.5 and a general hardness of 10–25 dGH. A moderate water flow is preferred. To replicate their natural habitat, the tank should include plants - densely covered and plants - floating.
As a schooling species, Red Rainbowfish should be kept in groups of at least 6. Keepers should be aware that this species is a known jumper, so a tight-fitting lid is essential. This species is available in 2 varieties: Male (Standard) 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.
Similar Species
Turquoise Rainbowfish
Melanotaenia lacustris
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.
Boeseman's Rainbowfish
Melanotaenia boesemani
An incredibly popular and active schooling fish endemic to the Ajamaru Lakes in West Papua, Indonesia (currently listed as Endangered in the wild by the IUCN due to overfishing and habitat loss, though commercially captive-bred). Famous for the mature male's spectacular blue and orange split-coloration. They require long tanks for active swimming, excellent oxygenation, and warm, hard, alkaline water to thrive.
Threadfin Rainbowfish
Iriatherina werneri
A delicate and exquisitely shaped nano rainbowfish native to New Guinea and Northern Australia. They are famous for the males' long, filamentous fins and butterfly-like display behavior. Due to their incredibly small throats, they require micro-foods. They are shoaling fish that are easily intimidated by boisterous tank mates.
Dwarf Neon Rainbowfish (Praecox)
Melanotaenia praecox
A brilliant, active schooling fish native to the Mamberamo River basin in West Papua. Known for their iridescent neon-blue bodies, they are an energetic and peaceful addition to community tanks. Because of their high activity levels, they require ample open swimming space alongside planted areas. They are fast eaters and may outcompete shy tank mates for food.
Japanese Ricefish (Medaka)
Oryzias latipes
A hardy, small, and colorful fish native to East Asia. Extremely popular in the outdoor pond hobby and nano aquariums. They are 'amphidromous' (tolerant of salinity changes) and can survive a wide range of temperatures, making them excellent tub/pond fish. They are surface dwellers that look best when viewed from above (top-down).
Cardinal Tetra
Paracheirodon axelrodi
A stunning schooling fish native to the upper Orinoco and Rio Negro basins in South America. Famous for its brilliant iridescent blue line and a vivid red stripe that extends the full length of its body (distinguishing it from the Neon Tetra). They are strictly schooling fish that thrive in warm, acidic blackwater environments.