The Churaumi Aquarium in Okinawa, Japan, has a fish tank so big that it's called the Kuroshio Sea. The gigantic tank is 10 m (33 ft) deep, 35 m (115 ft) wide and 27 m (89 ft) long and holds the equivalent of 3 Olympic-sized swimming pools worth of water.
The tank is so large that not one, but four whale sharks live in it. The Daily Mail has more gorgeous photos of the aquarium exhibit: Link
I wonder if they would in a facility of this size.
(Well, you can put a bunch of *other* sea life in with a whale shark... and they won't get EATEN!)