Built between 1933 and ‘35 as an open-air public aquarium, the Key West Aquarium, placed at the shoreline of Key West Harbor, poses a unique set of challenges to maintain over 30 exhibits of marine life in a historical facility. Originally built in a remarkably efficient design, utilizing only two water pumps and a series of aqueducts, 21st Century technology has been retrofitted to allow more reliable water quality, and resilience in the face of ever-increasing storm impacts. Installations of a saltwater production well, degasification tower, injection well, and backup generator all while preserving the irreplaceable features of the building, provide a unique experience for guests, and importantly, the capability to provide habitats for iconic Atlantic species such as Tarpon, Goliath Grouper, Horseshoe Crabs, and Seahorses.