RAINBOW SHARK (Epalzeorhynchos frenatum)

A slightly better choice for the community tank than E. bicolor but tankmates must still be chosen with care.

While small specimens tend to hide away much of the time they become increasingly territorial as they grow and can display particularly high levels of aggression towards similar-looking species.



Some individuals may be more belligerent than others and there exist reports of apparent alliances with other species such as Chromobotia macracanthus. We’re unsure if these behavioural differences are indicative of gender but at any rate loaches from the genera Chromobotia, Botia, Syncrossus and Yasuhikotakia do seem to be left in peace by Epalzeorhynchos species whereas congenerics and members of Crossocheilus, Garra and Gyrinocheilus, for example, tend to be attacked constantly. Please note that in terms of the loaches not all may be housed together and proper research is essential.

Other bottom-dwelling fishes including cichlids and most catfish are best avoided as they may too be picked on. For the upper levels choose robust, active, schooling cyprinids. Ideally the Epalzeorhynchos should be the final addition to the tank in order to avoid it claiming ownership of the entire space.

This species probably lives a solitary lifestyle and in nature would probably have only come into contact with others of its own kind infrequently and during the spawning season. These instincts heighten as the fish get older and we therefore recommend it be kept singly in the majority of cases. In a very large tank with lots of cover a cohabitation attempt might be possible but each individual is likely to require a territory with a diameter of at least a metre.

https://www.seriouslyfish.com/species/epalzeorhynchos-frenatum/