Mitik is a baby walrus who arrived at the New York Aquarium just a couple weeks before Hurricane Sandy severely damaged the facility. Mitik survived the flooding of his enclosure and is ready for the aquarium to reopen on May 25. (Seth Wenig/Associated Press)

The New York Aquarium’s spot by the sea for the last 50 years has helped make it a special attraction, but last fall that location almost destroyed it.

Water from Hurricane Sandy flooded the aquarium’s carefully managed tanks with oily, dirty water. Power to the exhibits was knocked out, making it impossible for aquarium staff to check on the 12,000 animals for days. There was even talk of shipping the animals away.

But the happy ending to this story is that six months after the storm, more than 80 percent of aquarium’s collection remains intact, and visitors should be able to see walruses, angelfish, otters and other animals when about half the aquarium reopens May 25. There are also plans to expand and floodproof the aquarium, which is on Coney Island next to the Cyclone roller coaster.

As aquarium director Jon Forrest Dohlin walked through the 14-acre grounds recently, penguins watched from their outdoor habitat. Walruses snoozed as sea lions arced through the air on their trainers’ cues, staying in practice for when shows resume. Angelfish and other tropical species shimmered around a coral reef.

But the effects of the October 29 storm were still clearly visible.

You can see the sea lion’s reflection in a puddle of water on the floor of an exhibit that was flooded to the ceiling during Hurricane Sandy at the New York Aquarium. (Seth Wenig/Associated Press)

For example, the open pool in the front of the aquarium was dry; it had housed hundreds of freshwater koi that died in the saltwater surge.

Sharks, sea turtles and rays swam in a tank in the aquarium’s veterinary hospital. They’re healthy but were put there after the storm destroyed their exhibit.

Up to 15 feet of water swamped basements during Sandy. The pump house, which makes sure that the oxygen levels, temperature and water chemistry are right for the animals in each exhibit, wasn’t working.

None of the animals had been evacuated from the area. That would have been very difficult to arrange in the few days the aquarium had to prepare, Dohlin said.

Scrambling to save the animals, 18 staffers used hospital-style canisters to get oxygen into the water, rebuilt filters and pumps on the fly and called in equipment from four zoos. They mixed artificial seawater in garbage cans and warmed rooms with space heaters to keep water temperatures up.

At the same time, managers had to decide how much longer they could wait before sending the animals away, which could have been harmful to the already stressed creatures. But by November 3, key systems were at least partially running in all the exhibits, so the animals stayed.

The koi and some other fish had died. But many other fish and all the mammals were fine — including Mitik, an orphaned walrus calf that arrived only weeks before. He seemed to enjoy splashing in a couple of feet of surge water, Dohlin said.

A three-foot-long American eel disappeared from its tank but turned up, unharmed, in a shower stall. Seahorses held on to life despite the cold, dirty surge water that flowed into their tropical tanks.

Now, plans call for making changes so that the aquarium will never again flood.

— Associated Press