At a glance the quick version
Looks how to spot one
Deep-bodied serrasalmid with strong jaws
A sturdy, deep-bodied fish with a blunt head and a powerful bite. Adults are grey with silvery flecked scales on top and a red to orange belly, throat and paired fins. Young fish are silver with darker spots. Females tend to be a bit larger and rounder.243
Personality what they are like
More cautious than its reputation suggests. It lives in loose groups mainly for safety, settles into a pecking order, and is often shy in the aquarium. It is a species for experienced keepers and is best kept on its own or in a group of five or more without other fish.23
Daily activity how busy a day looks
Moderately active; larger fish are most active around dawn, dusk and at night.1
Grooming and care the hands-on bits
Has very sharp teeth, so take care during tank maintenance. Strong filtration and regular water changes keep conditions good for this large, messy eater.13
Home where they are happiest
A very large aquarium, at least 240 x 90 cm footprint (about 1,300 litres) for a group, with plants and cover. Water 24-28 C, pH 5.5-7.5, hardness 2-12 dGH.31
Food basics what goes in the bowl
Omnivorous and opportunistic: fish, insects, worms, crustaceans, snails, plus fruit, seeds and plant matter. In captivity feed foods such as prawns, earthworms, bloodworm and fish pieces rather than live feeder fish or mammal meat.243
Company who they like around
Keep singly or in a group of at least five; juveniles shoal while adults form looser groups.3
The story where it all began
Austrian zoologist Rudolf Kner described the red-bellied piranha in 1858 and named it after the naturalist Johann Natterer, who collected in Brazil. Its fierce public image largely traces back to a staged feeding display shown to Theodore Roosevelt in Brazil in 1913.213
Fun facts for the dinner table
- 1
Red-bellied piranhas talk to each other with sounds, including bark-like calls during face-offs and drum-like noises while competing for food.2
- 2
Teeth are replaced on alternate sides of the jaw, so the fish can keep feeding while new teeth grow in.1
- 3
Pairs build bowl-shaped nests about 15 cm across in the riverbed for their eggs.4
- 4
Much of its diet comes from scavenging, and it also eats fruit, seeds and plants.2
Recognised by the official bits
- IUCN Red List
- Assessed as Least Concern (December 2020)1
- Legal status
- Keeping is prohibited in some places, for example California and Washington in the USA; check local rules before buying2
The care rhythm a typical week and year
A typical home-care rhythm for a Red-bellied Piranha. A starting point, not a vet's advice.
- Feedingevery day
- Water changeAbout 30 to 50% of the waterevery week
- Water testevery week
- Filter rinseevery 2 weeks
Owner questions the things everyone asks
How often should I feed my Red-bellied Piranha?
Furry Diary's starting plan is to feed your piranha once a day. This works well for this moderately active fish, but you can adjust based on its appetite and the food label. Always ask your vet for advice on portion sizes.1 Pet Wiki plan
What does a Red-bellied Piranha eat, and what should it never eat?
Your piranha is an omnivore and enjoys foods like prawns, earthworms, bloodworm, and fish pieces. It should never be fed live feeder fish or mammal meat, as these can cause health issues. Stick to a varied diet of safe, prepared foods.243
How much space does a Red-bellied Piranha need?
A single piranha or a group needs a very large aquarium, at least 240 x 90 cm in footprint (about 1,300 litres). This gives them room to swim and establish their pecking order. For a group of five or more, this size is essential.31
What temperature, light or water does a Red-bellied Piranha need?
Keep the water temperature between 24-28°C, with a pH of 5.5-7.5 and hardness of 2-12 dGH. Provide plants and cover for shyness, and use moderate lighting. These conditions help your piranha feel secure and active.31
How often should I clean a Red-bellied Piranha's home?
Furry Diary's starting plan suggests a weekly water change of about 30-50% and a filter rinse every two weeks. Regular cleaning is important because piranhas are messy eaters. Test the water weekly to keep conditions stable.13 Pet Wiki plan
Can a Red-bellied Piranha live with others?
Yes, but only with its own kind in a group of at least five, or kept singly. They are best without other fish, as they are for experienced keepers. Juveniles shoal, while adults form looser groups with a pecking order.23
How long does a Red-bellied Piranha live?
Lifespan varies widely depending on care and environment. For a specific estimate, ask your exotic-pet vet or a good breeder who knows the fish's history. With proper care, they can live many years.
Can I handle a Red-bellied Piranha?
No, you should never handle this fish. It has very sharp teeth and a powerful bite, so always take care during tank maintenance. Use tools and nets to avoid direct contact.13
Written from the sources on this page, a few checked guides (VCA, ASPCA, RSPCA) and Pet Wiki's own starting care plan. A friendly guide, not a vet's advice.
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Silver DollarWhere this comes from
Every fact on this page has a numbered source. Spotted an error? [email protected].
- Pygocentrus nattereri, FishBase fishbase.seused for distribution, max length and weight, water parameters, IUCN status, teeth, activity, author and etymology
- Red-bellied piranha, Wikipedia en.wikipedia.orgused for size, colours, history, sounds, diet, legal status
- Pygocentrus nattereri, Seriously Fish seriouslyfish.comused for origin, size, tank and water parameters, diet, behaviour, history
- Pygocentrus nattereri, Animal Diversity Web animaldiversity.orgused for colours, diet, nesting
Checked 2026-09-30. Text is written in our own words from these sources.