The Borneo Redfin Silver Shark, scientifically known as Cyclocheilichthys janthochir, is a striking freshwater fish native to the rivers and floodplains of Borneo and Sumatra. This species is part of the Cyprinidae family, which includes many popular aquarium fishes. It is appreciated for its elegant body shape, silver coloration, and the distinctive red fins that give it its common name. Despite its name, it is not a shark but gets the moniker from its sleek appearance and fin shapes, reminiscent of marine sharks.

Cyclocheilichthys janthochir can reach a considerable size in adulthood, making it suited for larger aquariums that can accommodate its need for swimming space. This species is known for its peaceful temperament, making it a good candidate for community tanks with other large, peaceful species. However, due to its size and activity level, care should be taken to select tank mates that are not too small or aggressive.

The natural habitat of the Borneo Redfin Silver Shark includes river systems with clean, flowing water, which should be mimicked in the home aquarium. A setup with ample swimming space, moderate to strong water flow, and a well-oxygenated environment will help mimic these conditions. Decorations should include larger rocks and driftwood, though plants may be sparingly used as this fish requires plenty of open water for swimming.

The diet of Cyclocheilichthys janthochir is omnivorous, with a natural inclination towards consuming a variety of foods, including insects, crustaceans, and plant matter. In the aquarium, they should be provided with a balanced diet consisting of high-quality pellets or flakes, along with live or frozen foods such as brine shrimp, bloodworms, and daphnia to ensure proper nutrition and health. Vegetable supplements can also be included to mimic the plant material they would consume in the wild.

Breeding the Borneo Redfin Silver Shark in captivity is considered challenging, with few reports of successful breeding in home aquariums. This is likely due to their specific environmental requirements and the need for large, mature specimens to initiate breeding behavior. The breeding process in the wild is not well-documented, but it is presumed to involve seasonal migration and spawning in floodplain areas, which can be difficult to replicate in an aquarium setting.

Caring for Cyclocheilichthys janthochir involves commitment to maintaining high water quality, with regular water changes and monitoring of water parameters to ensure a clean and stable environment. Given their potential size, a large aquarium is essential, along with companions that are appropriate in size and temperament.

In summary, the Borneo Redfin Silver Shark is a captivating addition to the larger home aquarium, offering aquarists the opportunity to keep a large, active, and visually striking species. While its care requires attention to space, diet, and water quality, the rewards of keeping such an elegant fish are significant, adding a touch of the exotic to the aquatic hobby.