Red-bellied Piranha

Pygocentrus nattereri

FreshwaterFish

Care at a glance

Temperature: 75–82°F (24–28°C)
pH: 6.0–7.5
Adult size: 12.6 in (32 cm)
Minimum tank: 160 gal (605 L)
Temperament: Aggressive
Social behavior: Schooling
Swim level: Middle
Difficulty: Difficult
Breeding: Medium
Rarity: Very rare
Origin: South America
Family: Serrasalmidae

Overview

This is a difficult fish that needs a big group and a big tank, 600 liters or more, with strong filtration to handle the mess. They are a shoaling species and get more nervous, not less, when kept alone or in pairs, so keep a group. They hold the middle of the tank and are jumpy rather than the relentless killers films suggest. Feed fish fillets, shrimp, and other meaty foods. Skip live feeders, which carry disease.

In the wild

Red-bellied piranhas live in South American rivers and lakes across the Amazon, Orinoco, and Parana systems, favoring slow or still water with plants, submerged roots, and plenty of cover. That cover doubles as hiding space and a hunting spot. In the tank they want a large footprint, dim lighting, and some wood or planting to feel secure. Keep the pH from 6 to 7.5 and temps in the mid to high 20s C.

Good to know

This is a serrasalmid in the family Serrasalmidae, known for interlocking triangular teeth and a strong bite. Adults reach about 32 cm. They are actually omnivores, eating fish, crustaceans, insects, fruit, and seeds in the wild, and they spawn by laying eggs that the male guards. The IUCN lists them as Least Concern.

Did you know

Much of the piranha's fearsome reputation is overblown. In the wild they often act as scavengers and are easily spooked, and the famous feeding frenzy is mostly a dry-season response to crowding and scarce food rather than normal behavior. Kept fish frequently hide from people and may nip each other's fins more than anything else.