Home / Fishes / Tetras, piranhas and pacus / Red-bellied piranha
No federal permit to keepRed-bellied piranha
Pygocentrus nattereri
Fishes › Tetras, piranhas and pacus (Characiformes) › Serrasalmidae (Piranhas and pacus)
The red-bellied piranha, also known as the red piranha (Pygocentrus nattereri), is a species of freshwater ray-finned fish belonging to the family Serrasalmidae, which includes the pacus, piranhas and related fishes.
Care at a glance
Species-specific values
Values researched for this exact species. Where they differ from the group guide below, follow these. Air, surface and water temperatures are listed separately, and each source is kept as published rather than averaged.
| Water temperature | 75–82 °F (24–28 °C) Seriously Fish aquarium recommendation; not a wild collection measurement. | 284 |
| Water pH | 5.5–7.5 pH Seriously Fish aquarium recommendation; not a wild collection measurement. | 284 |
| Water general hardness | 2–12 dGH Seriously Fish aquarium recommendation; not a wild collection measurement. | 284 |
| Maximum standard length | 350 mm SL Source maximum; not total length or a guaranteed adult size. | 284 |
| Minimum tank base | length: 240 cm; width: 90 cm Source aquarium recommendation for this large species; stocking must also account for group structure. | 284 |
| Social needs | Species-only setup; the source allows a single fish or a group of at least five, preferring the group. Adult groups have dominance hierarchies. | 284 |
Species-specific aquarium care
- Tank: At least 120 in long and 39 in front to back for one adult (adults commonly reach about 19.7 in / 50 cm).
- Water: Freshwater.
- Temperature: 73–81°F (range recorded for this species).
- pH: 5.5–7.5.
- Hardness: 0–20 dGH.
- Layout: An open-water swimmer: needs long, open swimming space with few obstacles.
- Diet: A predator: feed meaty foods sized to its mouth (frozen fish, shrimp, worms); it will eat tankmates that fit in its mouth. FishBase classes it as a carnivore.
- Safety: Can injure people (sharp spines, teeth or electric shock): use nets and care when working in the tank.
Calculated from this species' own FishBase record: tank size from its typical adult length and swimming zone, water values from its recorded ranges. The group guide below fills in general care.
Care guide
Species care notes
- Tank: a base of at least 94 × 35 in (roughly 342 US gallons); space needed is rated “very large tank”.
- Water: a fairly wide range, from slightly acidic to slightly alkaline, 75–82 °F, pH 5.5–7.5, 2–12 dGH.
- Behaviour: a shoaling fish best kept in a group of six or more; not a community fish.
- Difficulty: Moderate (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “Some aquarists maintain this species in bare-bottomed arrangements for ease of maintenance, but standard aquarium gravel or sand are both suitable substrates.”
- Tankmates: “Best-maintained alone, although adults do not tend to prey on much smaller fishes.”
- Breeding: “Wild populations exhibit two annual reproductive seasons, the first during the rising of the water level at the onset of the wet season, and the second during the low water period during November and December, when there is a sudden temporary increase in…”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Piranhas, pacus and silver dollars
Applies to most species in this group. Habitat: South American rivers. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- Large tanks with strong filtration; pacus grow to over 2 ft and outgrow almost every home aquarium.
Diet
- Silver dollars: plant-based foods. Piranhas: fish, shrimp and pellets.
Health watch
- Piranhas are banned in many states. Never release pacus.
Understanding the animal
About this animal
About this animal
The red-bellied piranha occurs in South America, found in the Amazon, Paraguay, Paraná and Essequibo basins, as well as coastal rivers of northeastern Brazil. This fish is locally abundant in its freshwater habitat.
Quoted from the Wikipedia article “Red-bellied piranha” (CC BY-SA 4.0) 174
In the wild
In the wild
From this species’ own FishBase record (habitat, bottom type, water and breeding data), not its family. Good care copies these conditions.1
| Where it lives | Lives in freshwater, in rivers and streams. Common in creeks and interconnected ponds in Matto Grosso, Brazil, where it influences distribution and feeding of other fish. |
| Water it lives in | Freshwater, 73–81 °F (23–27 °C), pH 5.5–7.5, hardness 20 dH. |
| Climate | Subtropical climate. |
| Wild diet | Hunting macrofauna (predator). |
| Behavior to plan for | Breeding: nesters. |
What this means for care
- Keep water within its wild range, 73–81 °F.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 91°F (up to 94°F in the hottest sampled areas) |
| Cool-season lows | about 66°F (down to 54°F in the coldest sampled areas) |
| Average temperature | 73–81°F across sampled records |
| Relative humidity | 73–83% on average (driest month about 70%) |
| Rainfall | about 1770 mm a year |
Measured at 526 wild occurrence records sampled against WorldClim 2.1 climate data (1970–2000 averages). Air conditions in the range are ecological context, not enclosure settings: microhabitats such as burrows, leaf litter or basking rocks can be cooler, warmer or more humid.
From the sources
From the sources
Quoted from the matching sections of reputable sources for this exact species. Specialist databases are used first; Wikipedia (community-edited, CC BY-SA 4.0) only fills gaps. Other sources are short credited quotes.
| Overview | The red-bellied piranha, also known as the red piranha (Pygocentrus nattereri), is a species of freshwater ray-finned fish belonging to the family Serrasalmidae, which includes the pacus, piranhas and related fishes. The red-bellied piranha occurs in South America, found in the Amazon, Paraguay, Paraná and Essequibo basins, as well as coastal rivers of northeastern Brazil. This fish is locally abundant in its freshwater habitat. They are carnivorous foragers and feed on insects, worms, crustaceans and fish. — Wikipedia (community-edited) |
| Where it lives | Home ranges Population dynamics Growth parameters Max. ages / sizes Length-weight rel. Length-frequencies Mass conversion Recruitment Abundance Life cycle Reproduction Maturity Maturity/Gills rel. — FishBase |
| Wild diet | Foraging methods vary in different life stages of P. nattereri. — Animal Diversity Web |
| Behavior | Pygocentrus nattereri encompasses a larger geographic area than any other piranha species, covering much of the Neotropical region. When red-bellied piranhas are introduced to other parts of the American continent, there are usually negative consequences for the local fish fauna, partially due to its generally aggressive behavior. This aggressive behavior is sometimes marked by the acoustic sounds they produce. — Wikipedia (community-edited) |
| Reproduction | Males and females appear externally alike & 9245). In ' Serrasalmus sp. aff. nattereri ', reported to occur in the Orinoco basin (Venezuela, Guyana), the males have more 'bull-like' heads, but are more slender than females. Eggs are laid on tree roots trailing in the water and are guarded; the reproductive success may vary strongly from year to year depending on how the savanna was flooded. — FishBase |
| Appearance and size | Maximum length 50.0 cm sl male/unsexed; maximum published weight 3.9 kg. — FishBase |
| Biology | Common in creeks and interconnected ponds in Matto Grosso, Brazil, where it influences distribution and feeding of other fish and in areas of high primary production in Rio Machado and Rio Negro. Adults feed mainly at dusk and dawn on insects, worms and fish. — FishBase |
| History and naming | The fish's binomial name is named after Johann Natterer. — Wikipedia (community-edited) |
| Conservation | Pygocentrus nattereri has been introduced to the freshwaters of the United States on numerous occasions. — Animal Diversity Web |
Data and studies
The numbers
The numbers
Each bar is what one source reports. Where several sources weigh in, the dashed gold band marks their average.
Typical adult weight
Average adult body mass in each database (FishBase gives the maximum recorded weight).
Adult length
Maximum recorded length. Measured as standard length (snout to the base of the tail, not counting the tail fin). Fish in home aquariums often stay smaller than wild records.
Water temperature
Range the species tolerates in nature; aim for the middle.
Water hardness
Minimum tank footprint
Seriously Fish recommends a tank base of at least 94 × 35 in (about 342 US gallons).
Veterinary & husbandry research
Veterinary & husbandry research
- New insights into patterns and rates of tooth replacement in serrasalmid and characid fishes, with implications for the subsistence fishery of Peru's remote ribereños villages Stuart CE et al., Journal of fish biology 2021
- Detection of betanodaviruses in apparently healthy aquarium fishes and invertebrates Gomez DK et al., Journal of veterinary science 2006
- Glomerulocystic kidney in two red piranhas Pygocentrus nattereri Sales-Ribeiro C et al., Diseases of aquatic organisms 2023
- Heterologous Production and Evaluation of the Biological Activity of Cystatin-B From the Red Piranha Pygocentrus nattereri Ramirez Merlano JA et al., Frontiers in genetics 2022
Peer-reviewed papers that mention this species alongside captivity, zoos, veterinary care or aquaculture. Some cover several species or mention it only in passing, so check the abstract. 170
Sources for this sheet
- FishBase (Froese & Pauly, eds.), version 24.07 Peer-reviewed researchThe global scientific database on fishes, maintained by a consortium of research institutions; every value is referenced.
- Seriously Fish species profiles Experienced keeper or breederLong-running aquarium reference written and peer-checked by experienced fishkeepers and ichthyologists; each profile covers habitat, tank size, water, diet, behaviour and breeding.
- Merck Veterinary Manual: Management of aquarium fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Merck Veterinary Manual: Types and features of aquatic systems Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Merck Veterinary Manual: Nutritional diseases of fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Wikipedia (species article) Community referenceFree encyclopedia; useful overviews with their own citations. Intro text is quoted under CC BY-SA 4.0.
- PubMed (U.S. National Library of Medicine) Peer-reviewed researchIndex of peer-reviewed veterinary, zoo and husbandry research.
- iNaturalist (captive observations) Community referenceCommunity observation platform run by the California Academy of Sciences and National Geographic; observations marked captive show animals living in homes, zoos and aquariums.
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