In Piranha 3D and Piranha 3DD, there are dozens of scenes of piranhas eating humans, but very few of them eating their fellow fish. With that in mind, Hasselfhoff noted that people need to find a way to morph into a piranha in order to survive the attacks.
He suggested buying a Halloween costume to disguise yourself as a piranha the next time you see them. Any way to confuse an attacking piranha could help provide you with a few extra seconds that you would need to get out of the water. In the new film, the scenes of piranhas eating fellow piranhas are few and far between, as the piranhas focus on their human targets. With that in mind, a piranha disguise might provide just enough cover to survive an attack.