How the Georgia Aquarium Works

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

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.


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 rostrum, 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.



Building the Aquarium

A great hammerhead shark in the Ocean Voyager tank. Even though sharks are predators, they don't typically feed on other animals in their tank as long as they are well fed.

Building the aquarium, a parking deck and exhibits for all these animals was no small task. In the process, the aquarium used:

  • 328 tons of acrylic windows, about the weight of two fully grown blue whales
  • 290 plumbing fixtures, 200 floor drains and 53 roof drains connected with 1.5 miles of underground pipe and 5.5 miles of aboveground pipe
  • 61 miles of pipe and wire
  • 100,000 yards of concrete and 2,500 auger-cast piles
A skylight over the Ocean Voyager tank lets the fish get natural sunlight on clear days. In this picture, the skylight's louvers are closed.

The Ocean Voyager tank, the largest habitat, holds three-fourths of the aquarium's water. It is 263 feet long by 126 feet wide by 33 feet deep, and it holds 6 million gallons of water. Pens at one end allow staff to separate fish from the rest of the tank, and veterinarians can examine larger animals inside them. A slow-moving conveyor belt takes visitors through a 100-foot acrylic tunnel under the tank, letting them view the fish from below.


Other aquarium exhibits include the 800,000 gallon beluga whale enclosure, smaller tanks and multiple touch tanks where visitors can get hands-on experience with aquatic animals. Many of the tanks use artificial light, but the Ocean Voyager tank, the beluga whale habitat and the large coral reef all receive natural light.

To fill the tanks, the aquarium piped in 8 million gallons of ordinary tap water -- enough to fill 160,000 bathtubs. After treating it to remove chemicals and impurities, the staff had to turn this fresh water into salt water for marine habitats. To do this, they added 750 2,000-pound sacks of Instant Ocean® sea salt, for a total of 1.5 million pounds. That's the equivalent of more than 920,000 containers of table salt.

To salinate the water for the marine exhibits, the Aquarium used 1.5 million pounds of Instant Ocean® sea salt. Keeping the water salinated requires very little additional salt.

Next, we'll look at where the aquarium found all of the animals that live in its tanks.


Acquiring the Animals

[b]Aquarium staff lower a beluga whale into its transport container.
Photo courtesy UPS

Like all zoos and aquariums, the Georgia Aquarium has received criticism from animal rights groups and others who believe that the animals living there would be better off in the wild. But about 70 percent of the aquarium's animals came from fish farms, zoos and other aquariums. In several cases, aquarium staff rescued animals that were living in unhealthy circumstances or that would have died without their intervention.

With the help of United Parcel Service (UPS), the aquarium staff moved more than 100,000 fish from aquaculture farms in Taiwan to a quarantine warehouse in a period of 36 hours. These fish flew in 42 specially designed tanks, and many of them were very small when they arrived.


Some of the aquarium's largest species also arrived via UPS. For example, Ralph and Norton, the aquarium's original whale sharks, and beluga whales Nico and Gasper made their journeys in specially designed tanks with life support systems. Ralph and Norton flew 8,000 miles from Taipei, Taiwan with a layover in Anchorage, Alaska on a specially equipped B-747 freighter jet. Nico and Gasper flew 1,331 miles from Mexico City, Mexico on a 767 cargo jet. Aquarium staff accompanied the animals on their journeys and moved them into and out of their containers using special slings. Flatbed trucks carried the enclosures from Hartsfield-Jackson International Airport to the Aquarium.

Aquarium specialists secure a whale shark in its transport container off the coast of Taiwan. Whale sharks are the largest known fish in the world, but these are still juveniles.
Photo courtesy UPS

With animals and water inside, the whale shark tank weighed 54,000 pounds, and the whale tank weighed 26,000 pounds. Because of all this weight, the airplanes required modifications to handle the load. UPS workers had to place the tanks precisely according to the planes' center of gravity. The weight also affected takeoff and landing speeds.

A specialized sling removes a whale shark from its transport container. Left in the wild, the sharks would likely have been caught for food.
Photo courtesy UPS

In addition to the whales, whale sharks and animals from aquaculture facilities, other live animals brought to the aquarium include:

  • A school of tarpon, silver fish that can weigh more than 300 pounds when fully grown, rescued from a tide pool
  • An unnamed species of fish, which is about 4 inches long and is orange with a pink tail, collected off the coast of Fiji
  • Several species of tropical fish rescued after the U.S. Fish and Wildlife Service confiscated them as an illegal shipment
  • A bowmouth guitarfish caught by accident by Taiwanese fishermen
  • Oz and Gracie, sea otters from the Oregon Zoo and California's Aquarium of the Pacific
  • Local species, like cownose rays, collected from the Georgia coast
  • Coral, grown for use in the aquarium rather than harvested from existing reefs

We'll look at where and how the staff prepares meals for these animals next.


Feeding the Animals

Aquarium staff feed African black-footed penguins. Several beads around the penguins' wings identify them. Males have a blue bead closest to their chest, and females have a pink bead.

Feeding the animals at the Georgia Aquarium is a lot more complex than just sprinkling a little food on the surface of the water. The aquarium staff prepares meals for all of its animals in the husbandry commissary, a specially designed kitchen that is held to higher standards than restaurant kitchens. The United States Department of Agriculture conducts random inspections of the commissary to make sure it is sanitary.

The husbandry commissary has a freezer that holds 20,000 pounds of food as well as a refrigerator that holds 6,000 pounds. The aquarium staff prepares food for the animals every day. Animal diets, amounts of food and the number of feedings per day vary widely from species to species. Some of the animals eat prepared food that resembles what they eat out of captivity, and others eat exactly what they eat in the wild. Many get vitamins or medicines in their food.


Bernie and Billi Marcus feed a whale shark.
Photo and video courtesy Georgia Aquarium

For example:

  • Leafy sea dragons eat exactly what they eat in the ocean -- small shrimp called mysids.
  • Whale sharks eat a special, pre-made gel food, as well as tiny crustaceans called krill. Whale sharks are filter-feeding fish, and they learned to eat from scoops before traveling to the Aquarium.
  • Beluga whales get four feedings of fish per day, and the largest eats about fifty pounds of fish divided among those four feedings.
  • Sea otters eat food-grade fish and clams. The biologists who work with the otters inspect their food for scrapes and cuts where bacteria can grow. Click here to see a video of one of the otters breaking open a shell to find food.

Aquarium specialists have access to the tanks to feed the animals, but the huge Ocean Voyager tank presents special challenges. It's roughly the shape of an hourglass, and it houses a wide variety of fish. Along with the whale sharks are species like great hammerhead sharks, sawfish, bowmouth guitarfish, grouper and golden trevally. In order to feed all these fish, the Aquarium uses a gantry crane, which runs on rails over the entire width of the tank. They set up feeding stations for each animal on the crane's platform. These stations let the staff make sure each animal gets the right amount of the right kind of food. As long as they are properly fed, even the most predatory species won't typically feed on smaller fish.

This gantry crane lets the Aquarium staff set up feeding stations for each species of fish in Ocean Voyager.

Feeding the fish high-quality food, customized based on what they eat in the wild and need to thrive in captivity, helps to keep them healthy. If a fish gets sick or injured, the aquarium has a complete veterinary facility and surgery on site. We'll look at these areas of the aquarium next. ­


Animal Health

The Georgia Aquarium surgical room.

The Georgia Aquarium's veterinary services and conservation medicine facility is like a teaching hospital where doctors get hands-on experience working with patients. It's a 5,800 square foot unit with 15 people on staff, and it houses 26 treatment tanks and a fully equipped surgery. The aquarium has a partnership with the University of Georgia and will provide a veterinary intern position and two three-year pathology residencies for the training of new aquatic animal specialists. The veterinary staff also conducts research on animal health and behavior and shares their results with other zoos and aquariums.

The laboratory and health facility can run blood tests on animals, examine slides under a microscope and culture bacteria for analysis. The surgery also has a mobile, digital radiography unit that can be moved anywhere in the facility and can x-ray animals as small as penguins and as large as whales. It has an ultrasound machine, an endoscope and machines that allow mammals, reptiles and fish to be anesthetized for surgery.


Preventive medicine is relatively new to the aquarium industry, but the Georgia Aquarium is working on preventive medicine protocols for all of its larger animals, including annual exams. Some animals, like beluga whales, which are prone to ulcers or to swallowing foreign objects, will receive routine endoscopies. Some animals may receive vaccines, although preventive medicine for aquarium fish generally relies on observation and quarantines for all new animals rather than vaccines.

A mobile, digital radiography system in the Aquarium's surgery. The x-ray emitter sends a signal to the plate, which sends an image to the screen.

All of the larger animals in the aquarium learn husbandry behaviors, which make it easier for veterinary staff to conduct examinations. For example, when a trainer instructs them to, whales will present their flippers or tail flukes for examinations or blood collection. They will also blow from their blowhole onto a plate, which staff can examine under a microscope for parasites and bacteria. When held, penguins will present their feet for foot checks. This makes it easier for the staff to do their work and considerably reduces stress on the animals.

Another requirement for healthy aquatic animals is the quality of the water in their enclosure. We'll look at fish life support and water quality next.


Fish Life Support

Some of the 218 pumps that help keep the water at the aquarium clean.

Even though the Georgia Aquarium's tanks hold 8 million gallons of water, the facility uses only as much water as an average supermarket. A treatment and reclamation system cleans and recycles the water, losing only a little to evaporation and the protein skimmers that help remove debris.

Behind the scenes, the aquarium uses three types of filtration:


  • Mechanical filtration, which removes fine particulates
  • Fractionation, which removes dissolved organic materials
  • Ozone, which plays the same role as chlorine in a swimming pool but is safer for fish

It takes 218 pumps, 141 sand filters and 70 protein skimmers to do this for the whole aquarium. These pumps move 261,000 gallons of water per minute -- that's about 163,125 toilet flushes. Ocean Voyager alone requires 28 pumps and 56 sand filters, which clean about 1,800 gallons of water per minute. The life support staff must perform maintenance, including oil changes and filter changes, on all of these pumps and filters.

This pump drives a protein skimmer.

The life support staff also measures tank turnover time -- the amount of time it takes for all the water in a tank to be filtered and cleaned. The staff's goal is to keep the turnover time under two hours. Flow rates also affect the dissolved oxygen in the tanks -- the fish will suffocate if there is too little, but too much can be toxic.

All these pumps send water through a series of filters and skimmers. Even though this process is necessary, it can also create some problems. We’ll examine filtering and monitoring in the aquarium’s life-support systems in the next section.


Filters and Skimmers

The protein skimmer produces foam. Debris clings to this foam, and when the foam overflows it takes the debris with it.
The high performance liquid chromatography system can measure antibiotic concentrations and anything abnormal that appears in the water. The laboratory staff will use it for research.

The sand filters are similar to what you would find in a home swimming pool, but on a much larger scale. The pumps force water through the sand at 15 to 20 psi, and the sand traps debris. The system can automatically backwash sluggish filters, and the staff changes the sand periodically.

In a protein skimmer, water from the exhibits passes through the filter, which injects air at a very high velocity. A venturi valve -- a tube with a constricted area in the center -- breaks the air into micro-bubbles. These bubbles have a lot of surface area for debris to cling to. The foam that this process creates overflows from an opening at the top of the filter and falls into a collection chamber, which the staff must clean periodically. Check out this Marine Depot article for more detail about protein skimming and venturi valves.


This process naturally requires a lot of pumping, which can produce dissolved gasses that are harmful for fish. So, the system pumps water up into holding tanks above the exhibits and allows the dissolved gasses to dissipate. Then, gravity pulls the water back into the habitats. Heating or cooling a small amount of water before return to the exhibits helps keep them at the correct temperature.

This system sounds complex, but a computer handles nearly all of the decisions regarding clean and dirty water. Eleven computers connected throughout the building make 150 million decisions per second involving tank levels, temperatures and pumping flow, all of which are critical to animal health and system operation. The computer uses graphics and data to provide information and feedback to the life support staff.

Even though the system is almost 100 percent self-sustaining, the staff still takes samples from every exhibit every day, analyzes them in a lab, and adds any necessary chemicals by hand. Water chemists evaluate the nitrogen cycle -- the breakdown of organic material into nitrogenous wastes -- as well as ammonia levels, pH, salinity and oxygen in water samples from every habitat every day. An ion photography system measures, dilutes and analyzes samples, recording anything that is positively or negatively charged. The staff also uses a high performance liquid chromatography system for research-based applications.

Research is important to the aquarium's mission and to its status as a nonprofit organization. We'll explore other research and education programs in the next section.


Education and the 4R Program

Children investigate aquatic life in the Learning Loop.
Photo courtesy Georgia Aquarium

It's hard to miss the educational focus when you visit the aquarium. Every exhibit has signs or touch screens with information about its inhabitants. The aquarium also has education stations to offer additional information to the public. Touch tanks, staffed with employees and volunteers, give people the chance to touch and interact with the aquarium's animals. In several areas, projectors display information about the animals along walls and floors. The aquarium also offers behind-the-scenes tours in which visitors can see how the aquarium feeds and cares for fish.

But, beyond the visitor areas, 25 percent of the aquarium is devoted to research and education. The Learning Loop, a space with learning labs and hands-on activities for students in different age groups, comprises an entire floor. The Learning Loop also offers summer professional development classes for teachers. All educational programs take place in the Learning Loop, separate from aquarium visitors. Officials estimate that 70,000 students will participate in programs there every year.


[b]A beluga whale in the 800,000 gallon whale habitat. Beluga whales live exclusively in arctic and sub-arctic waters, so the water in their tank is always 55° F/13° c.

The aquarium's 4R program is another avenue for research, conservation and improving fish life in captivity and in the wild. The four Rs are rehabilitation, relocation, rescue and research. Donations to the program support actions like the rescue of Nico and Gasper and their relocation to Georgia. In that case, three donors pledged $50,000 each, contingent upon a dollar-for-dollar match from the community, to rescue and relocate the animals.


Funding and Running the Aquarium

The Georgia Aquarium

The Georgia Aquarium started with The Home Depot founder Bernie Marcus. Marcus wanted to present a gift to the city of Atlanta and the state of Georgia, one that would encourage education and economic growth. In November of 2001, he announced his plan to build an aquarium in downtown Atlanta. He and his wife Billi donated $250 million toward the Georgia Aquarium's construction.

But they didn't do it alone. Marcus and aquarium staff visited 56 aquariums in 13 countries to do research and gather ideas. They also received financial contributions from AirTran Airways, BellSouth, Georgia-Pacific, The Home Depot, Southern Company and SunTrust Bank, which sponsored the aquarium's five aquatic galleries and its 4-D theater. Turner Broadcasting System sponsored the Learning Loop. People contributed through the Aquarium's FishScales program, and other corporations, like UPS, made in-kind donations. Even the land was a donation -- nine acres came from The Coca-Cola Company. With all this financial help, the aquarium opened debt-free.


Groundbreaking for the aquarium took place in May 2003, and it opened to the public on November 23, 2005. Construction of the 550,000 square foot facility took only 27 months, and a 1,600-car parking garage was built at the same time. In addition to the animal habitats, the aquarium houses a gift shop and a 4-D theater. It also has a 16,400 square foot ballroom and food-service kitchens. The heating, ventilation and air conditioning (HVAC) system, which must precisely maintain temperatures around the animal habitats, can make 9,000 decisions per minute and has a capacity equivalent to 1,200 average-sized homes.

A whale shark swimming with a school of golden trevally. Backstage tours at the aquarium give visitors a chance to see the sharks from above.

More than 200 people work at the aquarium, and about 1,000 trained volunteers donate their time. The aquarium has security staff as well as 99 video cameras and 97 proximity card readers. Everyone who visits the aquarium must go through a security check, and guns, knives, matches and lighters are not allowed inside. To further protect the safety of the fish, the aquarium prohibits straws, which can be harmful if thrown into exhibits, from the on-site restaurant, Café Aquaria.

Marcus and the aquarium staff hope that the aquarium will be completely self-sustaining, able to support itself through admission fees and rental of the ballroom and other meeting spaces.

Check out the links on the next page for lots more information about the Georgia Aquarium and aquatic wildlife.


Frequently Answered Questions

Is the dolphin show free at Georgia Aquarium?
The dolphin show is not free at Georgia Aquarium.
Why is the Georgia Aquarium famous?
The Georgia Aquarium is famous because it is one of the largest aquariums in the world.

Lots More Information

Related HowStuffWorks Articles

More Great Links


  • Georgia Aquarium site visit and staff interviews, November 2005
  • BellSouth Newsroom
  • Judy, Scott. "The Georgia Aquarium." Southeast Construction. March 2005.
  • Tharpe, Jim. "Aquarium's Lofty Goal: Save the Planet." Atlanta Journal-Constitution. August 14, 2005.
  • Tharpe, Jim. "Surprise at Aquarium." Atlanta Journal-Constitution. June 14, 2005.
  • Tharpe, Jim. "The Upkeep Costs Plenty." Atlanta Journal-Constitution. November 20, 2005.
  • UPS Newsroom,1360,,00.html