This is a spectacular aquarium with all the fish you will see snorkeling/diving and more. Lots of other exotic sea life. They have a lot of interactive exhibits that allow you to touch the sea life, swim with the dolphins (for an extra charge), or feed the sharks encased in a cage. They also will video tape the experience for you.
Kids love this exhibit as it is very children friendly. Its not too large to take up your entire day but you will enjoy it.
It is located in one of the nicest malls in Cancun where you can also dine at a selection of great restaurants.