Quetzo is the underwater city that is ruled by the parents of Flipper. It is home to many aquatic creatures.
Almost identical to the city of Atlantis, Quetzo has many buildings underwater. Quetzo was actually a sunken island that is home to many sea animals. The animals range from crabs, fishes, sharks, rays, and other species.
During the events of the third season, Flipper and Lopaka realized that the city was sunk long ago when the king brought the statue of Neptune and the trident to the surface. After a while, the curse of Neptune's trident is unleashed towards the city. Flipper and Lopaka must bring it back to the abyssal zone to save the citizens.