Piranha
(Serrasalmus nattereri)

Piranha or Serrasalmus nattereri were originally assigned to the family Characidae which includes tetra varieties. They were later reclassified to a subfamily of Characidae, the subfamily Serrasalmidae. Serrasalminae means “serrated salmon family.” This refers not to the piranha’s teeth but to the serrated keel running along the belly of the fish.

Piranhas are native to the South American rivers and can be found in the Amazon, Orinoco, Guyana, and Sao Francisco river systems.

Piranhas are illegal to own in most the states in the United States for fear that they will make their way into the wild and reek havoc on the ecosystem, not to mention swimmers. This concern is not entirely unwarranted. In the past, irresponsible hobbyists have released piranhas into the wild because they have outgrown their tanks. When I was young, you could buy baby alligators at the local dime store. Hmmm…, what do you do with them when they get big enough to eat the neighbor’s dog? Vermont is one of the few states that allow the keeping of piranhas.

If you wish to raise piranha, check on their legality with your state’s Fish and Game Department. Piranhas are sometimes smuggled into the U.S. under falsified invoices identifying them as baby pacus which they bear a striking resemblance to. Be forewarned: If you are caught in the possession of an illegal piranha you could be facing a hefty fine or possibly even jail time.

The word piranha conjures up images of a bloodthirsty pack of savage killers that will strip a fully grow cow down to its skeletal remains in a matter of minutes. In reality, piranhas are shy, rather skittish fish. They rather spook easily. Their savage ferocity while feeding is greatly exaggerated. Studies have shown, in fact, that they are a benefit to the ecosystems which they inhabit, filling a necessary spot in the food chain.

In their natural habitat piranhas are just as likely to feed on insects and worms as they are other fish or animals that stray into their path.

Contrary to popular belief, not all piranhas travel in packs. Black Piranhas are solitary fish. The Red-bellied piranha, on the other hand, does hunt in packs. They usually hold back until a single member of the group initiates the attack. This initiator is commonly referred to as a scout. All things considered, the piranha is just following his instinctual behavioral patterns as the top predator in his ecological food chain.

It is this instinctual behavior that makes them a prime candidate for a mono-species aquarium. They are predators and will eat as nature intended them to. They have the very sharp, serrated teeth and strong  jaws of a hunting machine.

As fish native to South America, Piranhas prefer slightly acid water around 6.8 pH with ideal temperatures of 75-80 °F.

Piranhas are large fish. Depending on the individual species, the can grow be as large as 18 inches. They will live anywhere from 8-10 years. Though there have been reported cases of them living longer.