Given that watching fish can lower your blood pressure, it's practically a public service for Mandalay Bay to provide this facility in a city where craps tables and other gaming areas can bring your excitement level to dangerous heights. Unfortunately, it's just a big giant aquarium (though we admire the style -- it's built to look like a sunken temple), which, hey, we like, but gee, not at these prices. (Though standing in the all-glass tunnel, surrounded by sharks and finny friends, was kinda cool.) Note also that it is waaay off in a remote part of Mandalay Bay, which might be a hassle for those with mobility problems.