The video recorded by Dutchman Martijn Mostert has been viewed more than 4,000 times, reports De Morgen.
The black-tip reef shark had been living in harmony with the bullhead shark for years, the Antwerp zoo told RTBF.
“Perhaps their instinct has taken over and the attacked bullhead shark was unwell,” said the Antwerp zoo. “They remain predators. As a precaution, the second bullhead shark was housed in another aquarium,” the zoo added.