White elephant fish can not be stewed. The walrus fish, is a South American tropical freshwater fish that lives in the Amazon River. The exterior is mostly gray with some red on the tail. It can grow up to 10 feet (3 meters) weighing 200 kilograms, ranked as the world's largest freshwater fish, but also one of the top ten most ferocious freshwater fish, known as dinosaurs in the water. It is rumored to have a history of more than 100 million years, and dinosaurs are contemporaneous animals.