The Piranha Fish - Species, Information, Care & Forum
Quick links - Answers
This page describes Piranhas and taking care of these fish when keeping them in aquariums and we also list FAQ, offer forum with question and answers, and pictures on this page! In addition we have following pages with detailed information about various Piranha species, you are welcome to visit them too: San Francisco piranha (Pygocentrus piraya), Orinoco piranha (Pygocentrus cariba), Red bellied piranha (Pygocentrus nattereri) with forum, Pinche piranha (Serrasalmus eigenmanni), Red Bellied Piranha article with large forum. Bear in mind we'd love to hear about your Piranhas and your experiences with this species, so make sure that before leaving Aqua-Fish.Net you leave a comment at the bottom of this page!
As everyone knows, the Piranha species is a very noted fish especially from TV. Its aggression and hunger for everything what moves in the water are well known facts. They are shown as cruel and merciless beasts in the TV. So why do people keep them? Aren’t such people only criminals who drop their victims into the tank with Piranhas in order to hide their crime? Not everyone knows that Piranhas bite only if they are hungry, or something bleeds in their aquarium. So basically, a wise and skilled fish keeper will not be bitten or even eaten (it’s a myth that few Piranhas can eat the whole man’s body). Their attacks towards humans are very rare in the wild. The natives from the locations where Piranhas live are swimming with them a lot and they haven’t been harmed. However, nowadays it is not recommended to do so because as the environment changes all around the world, the fish’ behaviour may change as well. Generally, they have less food so they can be much more aggressive against humans than before. There are no reports of killing a human by Piranhas, only when a human died in the water and they ate him later.
An illegal fish
Did you know that they are illegal in some states in the U.S.A? It is in the states with warm environment. Some people could put them into the rivers and they could destroy the normal environment in those waters because they would not have natural enemies there.
In order to understand this fish, we have to learn more about them
Piranhas are freshwater fish and they come from the Amazon, Guiana and Paraguayan basins in the South America where we can find innumerable living creatures (including fishes). These geographical locations are even the most settled places in the world, so you can imagine how much dead animals can fall into the water. This is the reason why Piranhas have to have such big appetite. Naturally, such rivers require fish which eat dead animals, so the decomposing meat will not contaminate the water. They have very sharp teeth so they can eat all the meat from the bones of the dead animal. Of course, they hunt for live food too, but usually smaller fish.
Conditions in the aquarium
In aquarium they require temperature between 24 – 28°C (75.20 - 82.40°F). The pH value should be a bit lower than 7, just like the dGH has to be lower than average (water hardness, water has to be soft). The aquarium has to have places for hiding; Something like caves, some driftwood, plants and everything what you can find in their natural environment besides a strong filter. They produce lots of excrements so the filtration must be very effective. They also need a big tank. If they haven’t got enough place they turn into cannibals.
Do they eat meat only?
There are many types of Piranha fishes. You can even find Piranhas which eat vegetables only (herbivorous fish). Moreover, we even don’t know all the Piranha species because new and new species are found often, however right now we know more than 70 different kinds of them. This differences are based upon the colours, and the behaviour as well. In addition, some of them are more and some are less aggressive.
They are from 15 to 30 cm (~ 6 - 24 inches) long. Piranhas can have many different colours and shapes of the fins, but they have something in common. The most visible characteristic are their teeth. Their mouth is a bit open and you can see their triangle small sharp teeth. They have round body with massive mouth.
In most cases this fish is a meat eater. A mature individual can eat pieces of fish meat, beef meat, chicken meat, or you can feed them with feeder fish especially if those fish are alive. But if they are small, they eat flakes and some worms. On the other hand, if you keep vegetarian piranhas, they eat plants in your aquarium, some vegetables, or vegetable flakes and tablets.
A community fish?
People think, that they are shoal fish and that they aren’t aggressive towards each other. But it is not true. They are in shoals only if they feel endangered, for example if they are chased by river dolphins, or if they are going to eat a big animal. They should not be in one tankwith other fish species because they will eat them. Of course there were some cases when smaller non-piranha fish have nipped fins of the bigger Piranha, but it is nothing strange when an aggressive fish is not aggressive to fish with which it has lived from the juvenile age. This must not be considered a rule, so you shouldn’t risk it. They are very territorial fish and because of this you should have them in a big aquarium so every fish has its own place.
Special thanks to Richard Smith for pictures!
Other interesting reading about Piranhas in aquariums
You should check the comments that can be found below in order to understand what's necessary to successfully raise Piranhas in your fish tank; Personal experiences are usually much more valuable than any article. You're welcome to submit your own experiences and ideas too! Apart from all information on this page, feel free to visit pages that exist on other websites; Piranha Fish @ AquariumOwner.Com, Pygocentrus nattereri - Red Bellied Piranha and Keeping Piranha both @ SeriouslyFish.Com, Piranha Fish Keeping for Beginners @ FishLore.Com, Red Piranha, Pygocentrus nattereri @ Animal-World.Com, Red Belly Piranha - Pygocentrus nattereri (Serrasalmus nattereri) @ AquaHobby.Com. If any of the links doesn't work, tell us about it, please.
Additional questions and answers
On March 19th 2011 we merged Piranhas-related questions from aqua-fish.net/answers with this article in order to offer more information at one place. If you want to ask something that hasn't been answered on this page already, feel free to use a form at the bottom of this page, please!
Which size of aquarium is required to keep Piranha?
Answer: If keeping a solitary Piranha, the minimum tank size should be 55 gallons (~ 255 litres, 66 US gallons), if keeping a group, the tank size should be at least 100 gallons (455 litres, 120 US gallons).
What is a piranha fish?
Answer: Piranhas are very common aquarium fish, although they live in the wild freely. The most known Piranha is the Red bellied piranha and some eat vegetable only, some eat meat only. They are not as aggressive as it's usually believed.