Fifteen bonnethead sharks at the Indianapolis Zoo died early Tuesday after an overdose of chemicals was added to their tank.
The sharks were found dead Tuesday. Vets at the zoo said that the sharks died as a result of too much ozone (an oxygen molecule in an electrically charged state that oxidizes, or dissolves, organic waste products in a pond or fish tank.) A system in the sharks’ tank was taken offline for maintenance Monday night and was unable to provide an accurate signal to the ozone generator, which continued to add ozone to the water overnight.
Two emperor snappers also housed in the tank survived the incident.
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