Revealing mistake: When Nick has swam back to his water scooter, he climbs up and drives away and the shark comes up behind him. But look carefully behind Nick as he is climbing. The nose of the shark is visible during the whole scene, right under the surface. This proves that the shark was a dummy, waiting to come up.
Visible crew/equipment: When Nick gets out of his black jeep at the parking lot, crew members are reflected in the car door.
Revealing mistake: During the surf competition, while Tom is swimming away from the sharks, the water is calm, suggesting this scene was shot in a lake or pool. You can see it again while Nick is swimming back to his jet swimmer.
Other mistake: Several times throughout the movie people are looking into the camera. Mostly at the grand opening of Water World, and at the surf competition.
Factual error: The sharks in this movie growl. Sharks do not growl.
