According to official website, a public comment, Nanjing Underwater World is a marine life exhibition project integrating popular science and entertainment, which is jointly built by China and Singapore. There are more than 200 kinds of fish, tens of thousands of fish, 6 penguins, more than 20 temperate penguins, polar bears, arctic foxes and other animals. Due to the high maintenance cost of rare fish, tickets for Nanjing Underwater World are expensive.