The piranha fish can live in the aquarium. Small beauty and sweet in water.The young Piranhas will differ much from adult ones as they show red spots on a silvery body. The adult fish will show its wel known gold scales body. As dangerous as these fishes are whenever they smell blood, as harmless they are normally. But never put your fingers into the aquarium if you have an even slightly wound on: The fishes will bite tiny pieces of flesh out of your hand, and if they are numbered up to a few tousand individuals they can easily put a (wounded) horse to a skeleton.