The Grand Reef area was a major addition to Discovery Cove in summer 2011, and enables guests to get a close-up view of a range of exotic marine creatures. It spans 2.5 acres, much of which is dominated by a 1.2 million gallon saltwater aquarium. This is home to 125 species of fish, rays, and sharks, with over 7,000 fish living in the tank in total. The tropically-themed area also includes white sandy beaches, an island lined with palm trees and hidden underwater grottoes.

Guests can swim freely in Grand Reef's aquarium with angelfish, sardines, tangs and groupers. The area also features a separate tank filled housing reef sharks and venomous lionfish. Only a sheet of glass separates the two tanks, enabling guests to experience swimming alongside the more dangerous fish without coming into contact with them.

While entry to the Grand Reef is included with the price of admission to Discovery Cove, the park also offers an optional premium experience, the SeaVenture underwater walking tour. This sees guests donning dive helmets and following a submerged path 10 feet below the surface, taking in close-up views of the Grand Reef's inhabitants. As with the park's other paid-for extras, the experience is available to limited numbers of guests. Groups of up to 9 people can take part, with the tour lasting approximately an hour.