The Blue Line Rasbora, scientifically known as Rasbora sarawakensis, is a small and graceful freshwater fish native to the calm streams and rivers of Borneo. Valued for its sleek form, vibrant coloration, and peaceful temperament, it is a favorite among aquarists who enjoy lively schooling fish that add subtle elegance to planted or community aquariums. This species is easily recognized by the striking blue line that runs along the length of its slender, torpedo-shaped body, often accompanied by a soft silvery or golden base coloration. The contrast of the metallic blue stripe against the more neutral body tones creates a refined and attractive appearance, while small translucent fins contribute to its delicate, gliding movements. Males tend to display slightly more intense coloration than females, particularly along the lateral stripe and fins, making them more visually prominent in a group. In the aquarium, Blue Line Rasboras thrive in well-planted setups with open swimming areas. Fine gravel or sand substrates, along with driftwood and leafy plants, create a natural environment that encourages their natural schooling behavior. They appreciate subdued lighting and stable, clean water conditions, which enhance their coloration and reduce stress. Moderate water flow that mimics gentle currents can also promote more active and natural swimming patterns. As a schooling species, Rasbora sarawakensis does best when kept in groups. Keeping them together allows them to display coordinated swimming, interact socially, and feel secure, which also brings out their brightest colors. They are peaceful and can be safely housed with other small, non-aggressive fish such as danios, other rasboras, or dwarf rasbora species, creating a dynamic and harmonious community. Feeding is straightforward, as these rasboras are omnivorous and readily accept a variety of small foods. A balanced diet includes high-quality flake foods, micro pellets, and live or frozen options such as daphnia, brine shrimp, or microworms. Occasional vegetable matter, like finely chopped greens or algae-based flakes, can supplement their diet and promote overall health. Regular, varied feedings help maintain vibrant coloration and active behavior. Breeding Blue Line Rasboras in captivity is achievable under the right conditions. They are egg scatterers, typically depositing eggs among fine-leaved plants or spawning mops. Providing a group with adequate cover and a separate spawning area can encourage natural breeding behavior, and the eggs can be protected by removing adults or using a breeding tank. Fry can be fed infusoria or finely crushed flake food until large enough for standard micro foods. The Blue Line Rasbora is an elegant, active, and peaceful species that adds color and movement to any aquarium. Its combination of shimmering lateral coloration, social behavior, and easy-going nature makes it a rewarding choice for both novice and experienced aquarists, particularly those looking to create naturalistic Southeast Asian-style community tanks.