I know that sometimes the 'theming' of an exhibit can be divisive, but this is a spectacular-looking whale habitat. I'm on the fence when it comes to cetacean captivity, but as a visitor I'd probably be awed.
It's definitely the best of the six exhibits I've seen in Asia. There are two other pools so I guess this represents about 40% of the total surface area? Whether it's truly 'big enough' is obviously subjective, but it didn't seemed cramped for the thirteen (!) animals they have.