The New Jersey Sea Life Aquarium at American Dream began filling its tanks with 250,000 gallons of water Wednesday -- and announced its opening date.

The “City Under the Sea”-themed venue, owned by Merlin Entertainment, will open to the public on Thursday, April 23.

Tickets for Sea Life went on sale in December and cost $21 for children and $26 for adults. Annual passes will start at $69.95.

The aquarium will feature a 13-foot tall replica of the Empire ‘Skate’ Building, a play on the famous Manhattan hotel, the Whale-dorf Astoria, and more iconic buildings. It’s largest tank will have various species of sharks, fish, rays and other sea creatures.

Camille DePascale, General Manager of New Jersey Sea Life Aquarium and Rich Weddle, its curator, started the tank filling with a ceremonial bucket pour into the grand ocean tank, then switched to large hoses to get the job done.

“The water fill is an exciting milestone for us because it takes us one step closer to opening day and gives a sneak peek into this one-of-a-kind Sea Life location with its ‘City Under the Sea’ theming,” said DePascale.

Once completely filled, the tanks will undergo different culturing and filtration processes to maintain water quality, Merlin said in a statement. The tanks will support salt, fresh and warm water creatures and feature approximately 75-100 different species of fish and invertebrates from local and international waters.

This will be the 10th Sea Life in the country and the first in the Northeast. The 25,000-square-foot New Jersey location will have 12 different exhibits with more than 3,000 creatures.

Merlin Entertainment unveiled the theming for the $30 million aquarium in November. The different zones will make visitors feel like they’re stepping onto a subway platform, walking along the Hudson River, on Wall Street and along Fifth Avenue.

Merlin Entertainments is the third largest entertainment company in the world, behind Disney and Universal Studios. It also owns Madame Tussauds celebrity wax museums and the London Eye.

It will also open a LEGOLAND Discovery Center at American Dream, beside the aquarium, this spring. It will consist of a LEGO-themed ride, 10 LEGO build and play zones, a 4D cinema and more. No exact date has been announced for that opening.

The aquarium is the newest opening announcement at American Dream in months.

The mega-mall in the Meadowlands began its phased opening Oct. 25 with the debut of Nickelodeon Universe and The Rink, an indoor NHL regulation-sized ice skating rink.

The DreamWorks Water Park was supposed to open Nov. 27 but has been delayed. No new opening date has been announced.

Then, Big SNOW ski and snowboard park, opened December 5.

American Dream developer, Triple Five, said in the fall that the retail and dining would open in March but no new information has been given.

See more of our ongoing coverage of the American Dream mega-mall here.

Allison Pries may be reached at apries@njadvancemedia.com. Follow her on Twitter@AllisonPries. Find NJ.com on Facebook.

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