Piranha keeping and feeding

Piranha (lat. Pygocentrus nattereri red-bellied piranha) — is a predatory fish kind and it belongs to Serrasalmidae subfamily, which is one of the most well known kinds of piranha.

These fishes live in a huge schools that spend the majority of time looking for a prey. The fish is rather gluttonous, therefore it can live only in the waters rich with fish.

More often red belly piranha can be encountered in some shallows, in the depth and in the muddy waters. Again, as one of the most known piranha kinds, it has a reputation of a freshwater predator, that is dangerous both to human and animals.

Habitat in the wild

Pygocentrus nattereri (that was earlier referred to as Serrasalmus nattereri and Rooseveltiella nattereri) was first described in 1858. There are lots of discussions and disagreements as for scientific name, so it’s quite possible that it may change later.

However, nowadays the fish is called P. nattereri. Habitat of pirahna is the river Amazon, Paraguay-Parana and North-West Brazil coastal river basins and Essequibo river basin as well. The basins of these rivers are in Argentina, Bolivia, Brazil, Paraguay, Ecuador, Guyana, Peru and Uruguay.

P.nattereri has a wide spectrum of geographical variations. Its South population is characterized with golden yellow abdomen and it’s often called P.nattereri «ternetzi», but it doesn’t make it a stand-alone kind of piranha (source).

This name appeared when Steindachner described a damaged holotype and named it Serrasalmo ternetzi. You can also rather often encounter a name «superreds».

Nevertheless, the fish coloring may change when being kept in a tank depending on the tank conditions and the feed received.



In the wild the fish grows to be about 30 cm (12 in) long and tank size is significantly smaller.

Its general lifespan is about 10 years, but the were some cases recorded when the fish lived to be over 20 years old.

Coloring depends on its habitat. The abdomen color varies from yellowish to reddish, when the rest of the body is silvery, golden or black.

The head can be of different shape and it notably depends on the diet. Some species have rather blunt shaped head and some have a small concavity above their eyes, which sometimes can be missing.

Fin size depends on the diet peculiarities and its habitat, – sometimes the fin can be very tiny.

Difficulties in keeping

Diet in captivity is rather simple, since the fish isn’t demanding as for the feed, so it’s quite easy to keep the fish in a tank.

However, we can’t recommend this fish for not experienced aquarists. The fish is large, predatory and you should be cautious even when maintaining the tank. There were some cases, when piranhas attacked and injured their owners. For example, when transporting the fish into other tank or etc.

Care and keeping in a tank

Scientific NamePygocentrus nattereri
Common NamePiranha, Red bellied piranha, red piranha
Tank size60 gallons (240L) and more
DietOmnivorous, Predatory
Temperature75–81 °F (24–27 °C)
Sizeup to 50 centimetres (20 in)

Piranha swims in all water layers. In a tank of 30 gallons capacity you can keep not more than one fish.

Taking into account the fact that it’s advisable to keep piranhas in a school of 4 at least species – the tank capacity for such a school has to be about 60 gallons and more.

Curiously enough, piranhas are rather timid, so to make them feel more comfortable, it’s required for the tank to have some places where the fishes can hide.

At that, it’s better to use snags and other tank decorations, since piranhas may damage tank plants.

The most important thing in care is that water should be always clean. Every week check ammonia and nitrates content in the tank water by means of tests and renew the tank water.

Water purity is crucial because the fish leaves quite a lot of leftovers when feeding and the feed contains proteins which start rotting rather fast. It’s also important to have a powerful external filter in a tank.


When chasing its prey the red bellied piranha relies on the speed and suddenness of the attack.

Sometimes piranha snooks its prey in a hide and attacks from it: all school of piranhas attacks the prey and eats it, at that each fish acts on its own regardless of any other school members.

The fish is well known for its nose which helps it to find a prey. Piranha easily smells blood near it.

In muddy water piranhas are dangerous to all animals that are within the fish sight. Fishes that become piranhas prey start to panic and try to escape one by one, but fast piranhas still catch them – they swallow the small ones right away and they tear pieces from the large ones and swallow them immediately to continue feeding.

A school of adult red bellied piranhas eats everything that comes on its way, the male fishes even eat water plants.

However, scientists have found out that red bellied piranhas don’t hurt any healthy catfishes of Hoplosternum kind. These catfishes fearlessly come close to piranhas and eat some parasites from their skin.

Piranhas feed is first of all fish; also they attack any mammals while they are swimming or drinking water, and birds which fly close to water as well.

In a tank red bellied piranha feeds on protein containing feed – fish, fish fillet, frozen prawns, calamary meat, heart, rain-worms and shed snakeskins, sometimes even live mice.

The fish everyday diet shouldn’t contain dry market feed, flakes or granules. Meat containing diet should prevail (fish, prawns, worms) with some addition of plant/vegetable components.

You have to be careful when feeding piranhas, since the fish may bite your hand.


The question if piranha can live with other fishes is one of the most controversial. One says that its impossible, the others successfully keep piranhas in a tank with very small fishes.

It’s more likely to depend on lots of factors: how large the tank is, how many plants are in it, the number of piranhas in the tank, their temper, diet and etc.

It’s easier to keep piranhas with large species: black pacu, striped raphael catfish, sailfin pleco, common pleco, bristlenose pleco.

The latter two are perfect tankmates, since they inhabit in bottom water layers and they are protected from attack with bone planes on their body. You may also try some other fishes as piranhas tankmates, but you never know…


Sex differences

It’s rather difficult to see between red bellied male and female. Visually you may see the difference only due to continuous observations of the behavior, especially during the spawning period.

Males become more brightly colored and the females abdomen becomes rounded.


Common piranhas that were bred in a tank, start to breed quite easily at the age of 18 month being 15 cm long.

Since it’s almost impossible to define the sex, the breeders buy about 6-8 species and grow them together. In some cases the male looks more dark colored than the female, which also has a yellowish abdomen.

Tank water acidity and hardness aren’t important when breeding, however the water temperature should be within 25-27° C.

Piranhas can breed in a community tank as well as in a separate spawning tank. In the latter case a tank of 40 gallons capacity should be used (60 gallons is even better).

The water is purified by means of powerful external filter and some small pebbles are put on the tank bottom as a substrate. It’s recommend to put some fluctuants in it, they’ll shade the tank and make the fishes feel more safe.

The beginning of spawning period is easily seen since the fishes start making a nest, their coloring becomes darker and they leave their school.

The spawning can be stimulated by adding some fish and fresh meat into diet and raising the water temperature up to 28° C. However, some aquarists decrease the water level first and then pour some fresh water for the same purpose.

During the spawning period the male fish makes the nest by removing gravel from the tank bottom, the female is swimming nearby at the same time. After finishing with the nest the male chases the female one till they reach the area which he has cleaned from pebbles.

They start swimming in circles and the female fish lays the eggs, the male fertilizes them. The clutch of 500-1500 eggs appears there in an hour.

Male takes all care about their offspring – he guards the eggs, fans it with his fins.

During the incubation period there’s no need to remove female from the tank. Piranha larva appears in two days after spawning and a week later red bellied juveniles start swimming.

It’s recommend to remove the juveniles into a separate 80 gallons capacity tank. Start feed for them can consist of brine shrimp nauplii and later you may feed them with blood worms and other live feed.