From the outside, Osaka Aquarium doesnot look that big, but it is home to more than30,000 creatures of 620 species includingotters, penguins, dolphins and two whale sharks.  The structure is a good design. It greets visitors with an underwater tunnel before the deep sea journey. The highlight is the Pacific Ocean tank (9m deep and 34m wide)that visitors can slowly view from the 8th floor to the 4th floor to see the whale sharks from every angle. They swim among other creatures like hammerhead sharks,spotted eagle rays and schools of mackerel,while some fish were sleeping on the sand bed. Although the tank is big, it seems to be toosmall to keep two whale sharks, the largest living fish. In addition, the aquarium also has tanks exhibiting Japanese spider crabs, mola mola or sunfish, various types of jellyfish and touch pools where visitors can touch some creatures like pitted stingray and brownbanded bamboo sharks.