The Georgia Aquarium is the largest aquarium in the world, whether you're measuring by the number of fish (more than 100,000) or the volume of water (more than a million cubic feet). It houses about 500 species in 60 habitats with 12,000 square feet of viewing windows, and it cost $290 million to build.

Rather than the traditional linear aquarium design, the Georgia Aquarium has five separate galleries arranged around a central atrium. They are Georgia Explorer, Tropical Diver, Ocean Voyager, Cold-Water Quest and River Scout. Tanks within the galleries house a diverse population of animals, including whales, sharks, penguins, otters, electric eels, rays, seahorses, sea stars, crabs and a variety of fish of all sizes.

A large coral reef in the Tropical Diver gallery. Much of this coral, specially grown off the coast of Fiji, is alive.

So how did they do it? How did they build habitats for all those animals, and where did they get all the fish? What does it take to keep the water clean and the animals fed and healthy? And how did the aquarium -- a nonprofit organization -- afford all that?

A largetooth sawfish in the Ocean Voyager tank. The sawfish eats small fish, crustaceans and mollusks. It uses its saw, or rostum, for attack, defense and digging for prey.

In this article, you'll learn the answers to these and other questions. You'll also learn about the aquatic animals that are the aquarium's star attractions.

­

Thank You! HowStuffWorks would like to thank the staff of the Georgia Aquarium for their assistance with this article. Special thanks to assistant veterinarian Megan Blasier, senior biologist Gina Fisher, senior life support operator Eric Hall, water chemist Anne Prusak, public relations director David Santucci, biologist Erika Stuebing and laboratory technician Jennifer Talarski.