Aquariums, Freshwater fish, Information, Rainbowfish, Species

Madagascar Rainbowfish (Bedotia madagascariensis)

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by Jason Matthews



The Madagascar rainbowfish is a freshwater fish well-known for its vibrant and captivating appearance. They are popular among pet fish owners due to their distinctive, colorful scales and lively behavior. Whether you’re a novice or an experienced fisherman, this species will capture your attention.

This article will delve into the fascinating world of the Madagascar rainbowfish, exploring its origin, appearance, size, behavior, tank conditions, diet, and much more. Come along and learn everything there is to know about this magnificent species.


Scientific Name: Bedotia madagascariensis
Common Names: Madagascan Rainbow Fish, Red-Tailed Silverside
Life Expectancy: 5-11 years
Adult Size: 5.9 inches (15.01 cm)


HabitatRivers, streams, and lakes
Care LevelModerate
DietPrimarily insect larvae, small crustaceans, and plant matter; accepts flake and frozen foods in captivity
Tank LevelMid to top
Minimum Tank Size20 gallons (75 liters)
Water pH6.5-7.5
Water Temperature73-81°F (23-27°C)
Water HardnessSoft to moderately hard water
LightingModerate to high lighting
Tank MatesPeaceful community fish such as tetras, rasboras, and livebearers

Fun Fact Corner

One interesting fact about Madagascar rainbowfish is that they exhibit unusual courtship behavior. Males will display their vibrant colors and swim in an elaborate dance to attract a female during breeding. 


Bedotia madagascariensis, the Madagascar rainbowfish, is native to the streams and rivers of Madagascar, a large island off the coast of East Africa. It is a freshwater fish that lives in Madagascar’s warm, clear streams and rivers. The region’s tropical climate and diverse habitats provide an ideal environment for the Madagascar rainbowfish to thrive, making it an essential component of the local ecosystem.

Appearance & Size

The Madagascar rainbowfish scales are iridescent and change color depending on the light angle, giving them a shimmering appearance. The species is typically blue, green, and yellow, with red or orange stripes running down its sides. This color combination gives the Madagascar rainbowfish a vibrant appearance that distinguishes it from other species.

The Madagascar rainbowfish has an elongated, streamlined body perfectly adapted for life in fast-moving streams and rivers. Their body shape, combined with their fins, allows them to navigate their environment and avoid predators easily. 


The Madagascar rainbowfish is a relatively small species, with adult fish typically growing to be around 5.9 inches long. This makes it an ideal choice for pet fish owners looking for a low-maintenance species that can thrive in smaller aquariums.


The Madagascar rainbowfish is a sexually dimorphic species, which means that males and females have distinct physical differences. Male Madagascar rainbowfish are more significant and brighter in color than females. Male Madagascar rainbowfish have elongated fins and a more pointed snout, distinguishing them from females.


The Madagascar rainbowfish is a social species that is peaceful and non-aggressive toward other fish. In the wild, this species lives in large schools, where individuals interact with one another regularly. This social behavior is also observed in captive populations, where Madagascar rainbowfish are often kept in groups.

These fish are known to be fast swimmers and are constantly swimming and exploring their surroundings. Despite its constant movement, the Madagascar rainbowfish is a non-intrusive species that will not interfere with other fish in the tank. The Madagascar rainbowfish is known for its curious nature. These fish are known to investigate their surroundings and will frequently approach their tank mates and objects. 


When choosing tankmates for Madagascar rainbowfish, it is important to consider the species’ peaceful nature and active swimming habits with similar water parameter requirements.

Here are some recommended tankmates for Madagascar rainbowfish:

Tank conditions

The Madagascar rainbowfish is a species that thrives in captivity as long as its tank conditions are properly maintained. These fish are native to Madagascar’s freshwater rivers and streams, requiring a similar environment in captivity.

A tank of at least 20 gallons is recommended for a small school of Madagascar rainbowfish. However, it is important to remember that these fish are active swimmers and will benefit from a larger tank. Furthermore, because Madagascar rainbowfish are social creatures that thrive in groups, selecting a tank large enough to house multiple individuals is best.

Madagascar rainbowfish are relatively adaptable to water parameters and can tolerate various conditions. Keeping the environment stable and the water clean and well-filtered is critical. The pH level should be between 6.0 and 7.5, and the water temperature should be between 72 and 82°F.

They do not require a heavily planted tank for decoration but benefit from natural elements such as rocks and wood. These elements can serve as hiding spots and create a more natural-looking environment.


These fish are omnivores and will benefit from a combination of meaty and vegetable-based foods. Madagascar rainbowfish feed on various small insects, crustaceans, and plant material in the wild. A diet consisting of high-quality flakes or pellets, freeze-dried or frozen foods such as bloodworms or brine shrimp, and fresh or frozen vegetables such as spinach or lettuce can provide a balanced diet in captivity.

Small, frequent feedings of Madagascar rainbowfish are preferred over one or two large feedings. This prevents overfeeding and water quality problems and more closely resembles the small, frequent feedings that these fish would receive in the wild.


Breeding Madagascar rainbowfish can be a rewarding experience for pet fish owners. These fish will breed quickly and display color and activity in the breeding tank with the right conditions.

In the wild, Madagascar rainbowfish breed during the rainy season, when food availability increases, and water levels rise. If the water conditions are favorable and there is an adequate food supply, these fish will breed year-round in captivity.

Providing a large and well-planted breeding tank for Madagascar rainbowfish is critical. The water conditions in the breeding tank should be similar to those found in their natural habitat, with a pH of 7.0 to 7.5 and a temperature of 22 to 28°C.

To mimic the conditions of their natural habitat, it is also necessary to provide a varied and nutritious diet and plenty of hiding places and surface vegetation. A healthy diet can help improve the health and vitality of the fish, increasing their chances of successful breeding.

Once the breeding tank has been set up and the water conditions are favorable, the fish will typically begin to pair off and lay their eggs on plant leaves or in the breeding caves provided. The eggs will hatch in 2-3 days, and the fry will be free to swim in another 2-3 days.


To prevent and treat diseases, maintain good water quality and watch for signs of stress or illness in your fish. Madagascar rainbowfish may be susceptible to common conditions, including parasites, bacterial infections, and fungal infections. 

Regular water changes, avoiding overfeeding, and using a high-quality water conditioner can help prevent many of these issues. If you notice any changes in your fish’s behavior or appearance, it’s best to consult a veterinarian experienced in fish health. Early intervention is key to successfully treating and preventing diseases in your Madagascar rainbowfish..


Jason Matthews

My name is Jason Matthews, and welcome to my website. When other kids were bragging about how their dog could sit and roll over, I was bragging about my latest Betta Fish and the cool sea castle I just added to his aquarium. 

Jason aquariume

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