Cartilaginous fish like sharks thrive in marine ecosystems across the planet, yet few have evolved to occupy lakes and rivers. Of the more than 1,000 species of Elasmobranchii (sharks, rays, and skates), only 5 percent can live in freshwater, and most of them do so part-time only. By comparison, Science explains, about 40 percent of bony fish (from goldfish to rainbow trout) live in freshwater. Researchers suspect it’s because of the metabolic costs of osmoregulation—having to maintain the right pressure by controlling water and salt concentrations in the body.
Only 5 percent , sorry but the chances kisames are the 5% that don't live in sal****er isnt good enough .