Downtown Aquarium was purchased by Landry's Restaurants, Inc. in 2003, when it was Colorado's Ocean Journey Aquarium. On July 14, 2005, Landry's reopened the redesigned complex as Downtown Aquarium. The entertainment and dining complex features a public aquarium boasting more than a million gallons of underwater exhibits that highlight fascinating ecosystems around the world. Downtown Aquarium houses over 500 species of animals, the interactive Stingray Reef touch tank, Aquarium Restaurant, Dive Lounge, the Nautilus Ballroom and amusements for the entire family. With a full-service restaurant, an upscale bar, a fully equipped ballroom, aquatic & geographic exhibits and shopping, Downtown Aquarium has it all! Downtown Aquarium - 700 Water St, Denver, Colorado, United States.