No other aquarium animals were affected. Ozone is pumped into the tank to kill bacteria and parasites and to clarify the water, but aquarium staff members are unsure why the ozone levels rose to dangerous levels.
"The exhibit has been open for nine years, and we've never had this issue happen before," Hamachek said.
The sharks, collected in the Gulf of Mexico, were two blacktip sharks, an Atlantic sharpnose shark and a blacknose shark.
