Ocean Animals Blood For The Sharks The biggest specimen ever measured is 18 meters long and weighed in at a ton 900 kg. It is the biggest invertebrate on the planet. The biggest differences between these two species of fish. The ocean sunfish is the largest bony fish on the planet. This gigantic fish feed mainly on jellyfish but will also feed on small fish and microscopic plant matter floating around in the water. This allows the large sunfish to tear apart its food so it can easily eat the smaller pieces. One of the biggest ocean animals ever, the Colossal Squid also has the biggest eyes at 25 centimeters (11 inches) across. The great white shark is at the top of the ocean food web because it eats large animals like small whales, seals, sea lions, squid and other smaller sharks.