Forget Sharks. The Terrifying Animal in New York’s Aquarium Is Lucy the Turtle "Sea turtles wreak havoc in aquariums, nipping keepers and eating sharks’ lunch" http://www.wsj.com/articles/forget-sharks-the-terrifying-anim...
At OldJob, they put in a small aquarium/whatever with two small turtles. One of the turtles died soon after, so they got a new turtle. Not too long after this, old turtle was seen holding the new turtle under water. New turtle died. Old turtle was taken home by a staff member who made sure that "Gacy" had an aquarium all to himself. ‎- bentley