One of the unfortunately very rare black water rasboras on offer is Rasbora cephalotaenia. The species is quite widespread on the Malay Peninsula to southern Thailand and on the large Sunda Islands (Borneo, Sumatra), presumably it is also found on smaller islands of the Sunda archipelago in suitable habitats. However, as peat swamps are drained all over South East Asia and used for oil palm plantations, this beautiful species is also endangered by environmental destruction.
As far as the water composition is concerned, Rasbora cephalotaenia are undemanding in themselves, at least as long as one does not want to breed; however, the beautiful colour marks, which are needed in the dark black water (practically no hardness, pH between 4 and 5) due to the poor underwater visibility to identify conspecifics, shine considerably more intensely in soft water tinted brownish by peat, dead leaves and alder cones.
Rasbora cephalotaenia grows to over 10 cm in length and is ideal for community aquariums, e.g. with harlequin barbs, labyrinths or catfish, given they are also blackwater inhabitants. The peaceful animals like to swim in a swarm with their conspecifics. They are free spawners without brood care. They eat all usual fish food. The water temperature should be between 24 and 28°C, for breeding 2-3°C higher.
For our customers: the fish have code 451602 on our stocklist. Please note that we only supply the wholesale trade.
Text & photos: Frank Schäfer