Vegas Aquarium Fish Love Being In Over Their Heads

Jeff Biggs floated in the gentle saltwater current while a yellow hose, snaking from his mask to the surface, provided him with life-sustaining oxygen.

Dozens of neon-colored tropical fish flitted around him, investigating this foreign visitor to their tranquil world.

Suddenly from his left, a 5-foot shark swam past Biggs, circled back and approached from his right. Biggs held out a chunk of fish to the shark, which gobbled it in one bite. Then the diver loosely wrapped his arms around the shark and swam up as if he were surfacing. After a few seconds, he released the shark.

Had Biggs been in the Atlantic Ocean or the Gulf of Mexico, his life might have been in danger. But since this was the 50,000-gallon aquarium in the Lost City of Atlantis attraction at Caesars on the Las Vegas Strip, Biggs was relatively safe from injury, save a nibble or two from a hungry snapper.

This dive was the second of two daily maintenance dives performed by staff at the Atlantis aquarium. The sight of a man swimming underwater with 500 fish--several of them poisonous--attracts a crowd even though it is a routine and necessary part of the aquarium’s upkeep.

It might seem simple: Fill a tank with a lot of water, line the bottom with fake rocks and plants, and put the fish in. But as anyone who’s ever owned a pet goldfish knows, it takes a lot of work to keep fish alive in a tank of water. Every detail, including the water’s contents and chemistry, is vital to creating and maintaining the perfect environment for sea life to thrive.

“It’s like a home aquarium except for the fact this is on a grander scale,” said Michelle Bogan, aquarium director. “You’re still performing the same tests. It’s a hard thing to do, though. I don’t know if I’d want to do it at home as a hobby.”

Water Requires a Delicate Balance

Despite the work and time involved in keeping an aquarium, several properties along the Strip have them, such as the 20,000-gallon aquarium in The Mirage lobby. The Rainforest Cafe in the MGM Grand keeps several small aquariums.

The biggest facility on the Strip is the 1.3 million-gallon Shark Reef at Mandalay Bay.

The maintenance principle is the same whether it’s 50 gallons or 1.3 million gallons of water, said Hugh Purgley, curator of Shark Reef.

At least once a day two divers, wearing 25-pound chain-mail suits, enter the water for an hour to scrub algae from the acrylic windows and aqua-scape, which simulates an environment from the wild.

“Seascaping is vital to some aquariums because some fish use it to hide,” Purgley said. “If you put fish in an empty tank, they would huddle in a corner. The animals are more at ease with strata.”

On this day at the Atlantis aquarium, Biggs is hand-feeding some of the fish, including the nurse shark, two stingrays and a lion fish with poisonous fins. The fish have to be hand-fed so the staff knows they’re eating properly. Biggs also is trying to get the shark accustomed to being handled by humans, in preparation for its eventual removal to a larger facility.

Once a week, a diver vacuums the aquarium gravel and cleans the algae from the glass.

“It’s all about balance and maintaining that balance,” Bogan said.

Because the Atlantis aquarium is home to 100 species of tropical fish, the saltwater must be kept at a constant 77 degrees.

A room underneath the aquarium houses a computer system responsible for monitoring the water’s temperature and acidity. At the slightest change, the computer automatically pages staff members. A mechanical and chemical filtration system are found there as well.

“Temperature is very, very important,” Bogan said. “Most of the cleaning is taken care of with the filtration system.”

Bogan relies on three types of filtration: bacterial, mechanical and chemical. The right level of bacteria must be kept in balance to ensure the health of the fish.

But even if the environment is perfect for tropical fish, an aquarium would fail if the species were incompatible.

“You have to know the social order of the animals,” said Biggs, the aquarium’s curator of fishes. He’s responsible for choosing the fish and introducing them into the aquarium.

“Animals getting eaten in public isn’t a good thing.”