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Maximum size : 10 cm

Ajamaru Rainbowfish - Melanotaenia ajamaruensis : Complete Fish Profile & Care Guide

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Ajamaru Rainbowfish (Melanotaenia ajamaruensis), with their lively nature and captivating presence, thrive in well-planted community aquariums, particularly when kept in shoals of six or more individuals. These active swimmers bring vibrancy to any aquatic environment. While they maintain a peaceful disposition with most species, their size and vigorous activity may appear intimidating, particularly to more timid tankmates. It's worth noting that while Ajamaru Rainbowfish may occasionally prey on Dwarf Shrimp, they generally coexist harmoniously with larger invertebrates that are not considered prey.

To create an optimal habitat for these remarkable fish, a spacious aquarium measuring at least four feet in length is recommended. This ample swimming space allows them to display their rapid movements and natural behaviour. Adding a dark substrate further enhances their striking colours, creating a captivating visual contrast.

The distinctive appearance of Ajamaru Rainbowfish showcases a remarkable blend of colours. Their reddish-brown hues adorn their body's back and anterior half, transitioning gracefully to shades of yellow or tan towards the posterior. Horizontal stripes in rich red-brown adorn their sides, adding to their overall allure. A metallic blue to yellowish or green base colour, combined with prominent yellow longitudinal stripes, completes their beautiful colouration.

Embrace the opportunity to create a flourishing aquatic community where Ajamaru Rainbowfish take centre stage with their captivating presence and stunning colours. Provide them with an environment that reflects their natural behaviour, and witness the harmony that unfolds within your aquarium's living tapestry.

Ajamaru Rainbowfish Photos

Sexual Dimorphism

Distinguishing between the male and female Ajamaru Rainbowfish is relatively straightforward. Mature males exhibit a strikingly vibrant colouration and possess a heightened first dorsal fin that extends beyond the origin of the second dorsal fin when depressed. Furthermore, males tend to have a deeper body structure compared to females, allowing for easier differentiation between the sexes.

Quick Facts

Scientific NameMelanotaenia ajamaruensis
Year Described1980
Other NamesAjamaru Lakes Rainbowfish
Max Size10 cm
Aquarium LevelMiddle - Top
DifficultyBeginner - Intermediate
Best kept asGroups 6+
LifespanUp to 5 Years

Water Parameters

Water TypeFreshwater
PH6.5 - 8.0
GH5 - 20
80 - 86
27 - 30

Natural habitat

The captivating Ajamaru Rainbowfish exclusively calls the Kaliwensi River in the Ayamaru Lakes of West Papua, Indonesia, it's home in the breathtaking Southeast Asian region. This locale boasts a myriad of small freshwater lakes and enchanting marshes, creating a haven for these remarkable aquatic inhabitants. Nestled within this scenic landscape, the Ajamaru Rainbowfish thrives, showcasing its vibrant beauty amidst the tranquil waters of its native habitat.

How to breed the Ajamaru Rainbowfish

To ensure the successful breeding of Ajamaru Rainbowfish, it is crucial to establish a dedicated breeding aquarium of the appropriate size. This aquarium should be equipped with a gentle air-driven sponge filter, providing the necessary circulation and filtration for optimal breeding conditions. When introducing the fish, a carefully selected group consisting of three females and two males should be acclimated to the breeding aquarium. To create an environment conducive to breeding, the tank should be adorned with an abundance of fine-leaved plants or clusters of Java moss, providing suitable surfaces for egg attachment.

Once settled in the breeding aquarium, the captivating courtship behaviour of the male Ajamaru Rainbowfish unfolds. Displaying an intricate dance, the male entices the female by swimming in front of her and guiding her over the lush plant life, utilizing the full extent of the tank. During this mesmerizing ritual, the female deposits a few relatively large eggs at a time, securely attaching them to the plants.

It is worth noting that Ajamaru Rainbowfish are known as "continual spawners," engaging in spawning activity over an extended period, spanning several days or even weeks. This characteristic presents a challenge for the aquarist, as some adult fish may exhibit cannibalistic tendencies towards the scattered eggs. However, providing the adults with ample food can help alleviate this behaviour.

Experienced fishkeepers have discovered the impressive resilience of Ajamaru Rainbowfish eggs. Some have successfully transferred the eggs to another aquarium using siphoning techniques, while others have used spawning mops. By capturing a cluster of eggs on the mop, it can be delicately moved to a separate tank, allowing for the subsequent collection of new batches of eggs.

Under optimal conditions, Ajamaru Rainbowfish eggs typically hatch within 6 to 9 days, with the exact timing influenced by the water temperature. Once the fry reaches the free-swimming stage, they can be nourished with infusoria, providing them with their initial sustenance. As they mature and develop, their diet can gradually transition to accommodate larger foodstuffs.

With meticulous attention to breeding details and a nurturing environment, the remarkable life cycle of Ajamaru Rainbowfish can unfold, bringing a sense of fulfilment and awe to the dedicated aquarist.

Diet & feeding

Ajamaru Rainbowfish are known to possess an omnivorous appetite, displaying a diverse palate that includes delicacies such as mosquito larvae, insects, small crustaceans, and zooplankton in their natural habitat. To ensure their health and enhance their vibrant colouration, a protein-rich diet comprising high-quality flakes and pellets serves as the foundation for their nutritional needs.

To further accentuate their innate beauty, incorporating occasional live food into their feeding routine proves highly beneficial. Including live food options like bloodworms, daphnia, and mosquito larvae two to three times a week contributes to the optimal display of their splendour. Feeding the Ajamaru Rainbowfish three times daily while keeping portions small fosters their overall well-being.

It is of utmost importance to provide only the amount of food that can be consumed within three minutes, as these fish prefer surface feeding. Furthermore, promptly removing any uneaten food prevents waste accumulation and helps maintain the optimal water conditions necessary for their thriving existence.

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