Care
Juvenile Harlequin Sharks (pictured) possess the most magnificent colours and markings. Sadly though, this eye-catching dress does somewhat fade with age. This species is also, unfortunately, most antisocial and should be kept as a solitary specimen. Never try and house more than one in the same aquarium, or with similar-looking species/other bottom-dwellers. The temperament of each individual does tend to vary from fish to fish, but on the whole, they can be extremely territorial and very troublesome towards other species, even those considerably larger than themselves and which you may have thought previously could hold their own. If, however, despite its unfriendly disposition, you would like to keep a Harlequin Shark, do ensure that it has a spacious aquarium in which to roam (6ft x 2ft x 2ft would be considered a minimum) with good filtration and a powerful flow rate. As a river-dwelling species, it will swim against the current in obvious enjoyment. Lighting should be fairly bright in order to encourage algal growth, which this species will graze upon with its fleshy mouth. The substrate should consist of fine sand or rounded gravel in order to protect this delicate mouth and sensory barbels. Sharp decor such as lava rock must be avoided. Darkened areas can be constructed out of bogwood and rocks, ideally providing the fish with many different territories to choose from. Plants can be included, although they should be of a robust nature to withstand the grazing behaviour of the Harlequin Shark. Many aquarists have had better success housing their Harlequin Shark with fast medium-sized robust tetras, barbs or danios rather than larger slower fish and similar bottom-dwellers, which usually succumb to relentless bullying. Due to the intensely territorial nature of this species, it is best to add this fish to the tank as the last specimen. It will persecute any newcomers to its environment. To sum up: This is a very beautiful large-growing species, and its keeping should be given much serious thought before deciding to take it on.
Feeding
Flake, sinking catfish pellets, algae wafers, frozen foods such as mosquito larvae, brineshrimp, daphnia etc. Browses on several different types of algae in the aquarium. Will graze on cucumber, spinach etc.
Breeding
There are currently no captive breeding reports for this egglaying species. It is unlikely to occur because of the unknown sexual differences and the intolerance of its own kind within the confines of the home aquarium.