Blue Line Rasbora Care Guide
Rasbora sarawakensis · Freshwater Fish
What Blue Line Rasbora look like
The Blue Line Rasbora (Rasbora sarawakensis) is a diminutive cyprinid fish characterized by its slender, torpedo-shaped body, reaching a maximum adult size of approximately 2 inches (5 cm). The body exhibits a translucent silver coloration, adorned with a striking iridescent blue-green horizontal line that runs along the midline, serving as a key identifying feature. This species displays minimal sexual dimorphism, although males may exhibit slightly more vibrant coloration during breeding periods. Defensive adaptations include a streamlined body that facilitates swift movement, allowing for quick escapes from predators. The species possesses a well-developed lateral line system, which aids in detecting water movements, and features a small adipose fin, contributing to its overall hydrodynamic profile.
Behavior & temperament
The Blue Line Rasbora is a highly social species, typically found in small to medium-sized schools within the water column of freshwater streams and rivers in Borneo. It exhibits a pelagic dwelling behavior, often occupying the mid to upper layers of the water column. This species is known for its active and playful temperament, making it a popular choice for community aquariums. Breeding behavior involves egg scattering, where females release eggs into the water column, allowing for external fertilization. The Blue Line Rasbora is generally peaceful, displaying minimal aggression towards conspecifics and other tank mates, although it may become skittish if kept in insufficient numbers.
Diet & feeding
In the wild, the Blue Line Rasbora is an omnivore, feeding on a varied diet that includes small invertebrates, algae, and detritus. In captivity, it thrives on a balanced diet of high-quality flake food, supplemented with live or frozen foods such as daphnia and brine shrimp to ensure optimal health and coloration.
Behind the name
Rasbora (from the Malay word for fish); sarawakensis (referring to Sarawak, the region in Borneo where it is found).
Plan your tank
Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.
Keeping Blue Line Rasbora?
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