Underwater World Singapore will be closing after 25 years, it announced yesterday, as the lease for the premises on Sentosa expires in less than two years.
The early closure of the aquarium on June 26 is to facilitate the transfer of the animals to their new homes, a spokesman for Underwater World said.
The Sentosa attraction faces competition from the new Marine Life Park and Universal Studios theme park, which are also located on the resort island.
The aquarium, run by Haw Par Corporation, has found a new home for its vulnerable or endangered marine animals.
"After nearly a year reviewing suitable facilities, we found a home for our pink dolphins, fur seals and otters," a Haw Par spokesman said.
They were moved to Chimelong Ocean Kingdom in Zhuhai, China, one of the largest marine parks in the world, on Sunday.
Chimelong was chosen as the Pearl River estuary near Zhuhai is one of the main habitats of the protected pink dolphins, also known as the Chinese white dolphin.
However, the search for suitable homes for other marine creatures at Underwater World is ongoing.
Haw Par also operates Underwater World Pattaya in Thailand, which is not affected, its spokesman said.
It does not look like there are plans for the site for now.
Sentosa Development Corporation said that following the decision by Haw Par to close Underwater World, it is "looking into refreshing the site with new and exciting experiences for all guests visiting Sentosa".
Mr Philip Chan, the senior supervisor of divers at Underwater World, was sad about the closure. "After caring for the animals for 25 years, I feel sad that Underwater World Singapore is closing. We'll all miss the fishes," he said.
According to its website, the attraction has 2,500 marine creatures across 250 species. They include sharks, rays, octopuses, turtles and many species of fish.
The aquarium will mark its closure with a month of charitable activities. It will give beneficiaries from charities it has worked with free admission to the attraction.
It will also lower ticket prices to its 1991 opening price from today - $9 per adult and $5 per child - against the usual prices of $29.90 for adults and $20.90 for children.
When Underwater World opened in May 1991, it was the largest tropical fish oceanarium in Asia. Built at a cost of more than $20 million, it was a big draw for tourists, and the opening bumped up visitor figures for Sentosa.
More than 30 million visitors have visited since it opened, said its spokesman.
Mr Allan Chia, who heads the Master of Business Administration programme at SIM University, said that Underwater World is a "micro attraction" as it is targeted only at people who want to see sea creatures.
Noting that Underwater World was a major attraction in the 1990s, when Sentosa did not have many attractions then, he said an issue now is that "there are other things like Resorts World Sentosa's attractions".
Dr Michael Chiam, senior tourism lecturer at Ngee Ann Polytechnic, said that because Underwater World's visitorship had dwindled over the years, the impact of its closure on the tourism industry "is not that great".
But there has been an outpouring of nostalgia since news of the attraction's closing broke on social media.
Geriatric occupational therapist Ummi Nurul Syafiqah, 21, said it is an iconic attraction in Singapore, comparing the aquarium to other landmarks such as the Merlion and the Esplanade.
Reminiscing about the attraction's underwater tunnel, Ms Syafiqah said that "one of the most awesome parts of Underwater World is that you could see sea creatures like sharks swimming above" as you walked along the tunnel or just stood on the travellator.