HomeFreshwater aquarium fishBarbs, danios & rasborasBlackline rasbora Blackline rasbora (Rasbora borapetensis) Scientific name: Rasbora borapetensis Smith, 1934 The Blackline rasbora (Rasbora borapetensis) is a freshwater fish of the family Cyprinidae that grows to about 5 cm (2 in). It is easy to keep and peaceful, suits community aquariums and needs a tank of at least 115 L (30 US gal), water at 22–26°C (72–79°F) and a pH of 6.5–7.0. Native range: Asia, Mekong, Chao Phraya and Meklong river basins. Blackline rasbora care at a glanceCare levelEasyTemperamentPeacefulCommunity tankExcellentAdult size5 cm (2 in)Minimum tank115 L (30 US gal)Temperature22–26°C (72–79°F)pH6.5–7.0Hardness5–12 dGH (89–214 ppm)DietOmnivore. Accepts flakes, frozen foods and live foods. BiologyDorsal soft rays (total): 9; Anal soft rays: 8. Has an incomplete lateral line, reaching at most to anal-fin origin; a dark brown mid-lateral stripe from gill opening to somewhat in front of caudal-fin base, not widening posteriorly and above it a second, pale stripe. No black pigment on fins.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameRasbora borapetensisFamilyCyprinidae (Minnows or carps)OrderCypriniformes (Carps)ClassActinopterygii (Ray-finned fishes)Maximum length6.0EnvironmentFreshwater;; pH range: 6.5 - 7.0; dH range: ? - 12 benthopelagicClimateTropicalDistributionAsia: Mekong, Chao Phraya and Meklong basins; also northern Malay Peninsula.Conservation status (IUCN)Not EvaluatedThreat to humansHarmlessUsesAquarium: commercialResilienceHigh, minimum population doubling time less than 15 months (tm More barbs, danios & rasborasGiant danioDevario aequipinnatusPearl danioDanio albolineatusDwarf rasboraBoraras maculatusHarlequin rasboraTrigonostigma heteromorphaClown rasboraRasbora kalochromaBrilliant rasboraRasbora einthoveniiSee all barbs, danios & rasboras Can it live with...?Blackline rasbora and Arulius barbBlackline rasbora and Brilliant rasboraBlackline rasbora and Clown barbBlackline rasbora and Clown rasboraBlackline rasbora and Coppernose barbBlackline rasbora and Dwarf rasboraBlackline rasbora and Giant danioBlackline rasbora and Greater scissortailBlackline rasbora and Harlequin rasboraBlackline rasbora and Pearl danioBlackline rasbora and Striped barb SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0. Aquarium care parameters compiled, checked and converted to metric and imperial units by Guppies.za.net.Last updated 28 September 2026