This document discusses several unique aquatic animals that hold records, including: 1. The whale shark, the largest fish in the world, which can grow up to 18 meters long and weigh 18 tons, yet is docile with its large mouth and tiny teeth. 2. The basking shark, a huge cartilaginous fish that stays buoyant by having a large liver filled with oil instead of an air bladder like bony fish. 3. The lanternfish, a small bony fish that produces bioluminescence and stays buoyant using waxy esters instead of an air bladder. 4. The Portuguese man o' war, which is actually a colony of organisms but