Home / Fishes / Tetras, piranhas and pacus / Spotted Piranha
No federal permit to keepSpotted Piranha
Serrasalmus marginatus
Fishes › Tetras, piranhas and pacus (Characiformes) › Serrasalmidae (Piranhas and pacus)
Care follows the piranhas, pacus and silver dollars guide below.

Care at a glance
Species-specific aquarium care
- Tank: At least 54 in long and 21 in front to back for one adult (adults commonly reach about 10.7 in / 27.1 cm).
- Water: Freshwater.
- Layout: Uses both the bottom and open water: give open swimming space plus cover near the substrate.
- 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.
- Availability: Rarely or never seen in the aquarium trade; expect to source it from specialists or not at all.
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 47 × 15 in (roughly 46 US gallons); space needed is rated “large tank”.
- Water: 72–77 °F, 5–15 dGH.
- Behaviour: temperament species tank; kept alone.
- Difficulty: Moderate (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “Best kept in a planted set-up with plenty of shaded areas.”
- Diet: “Wild fish feed mainly on the fins of other species as well as smaller fish, insects and crustaceans.”
- Tankmates: “Should only be considered as a specimen fish for the enthusiast.”
- Breeding: “Not thought to have been spawned in aquaria.”
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
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. Uses both the bottom and open water. Feeds mainly during the daytime, though some large fish (15-20 cm SL) extend their foraging activity to dusk (about 1800-1900H). Night is spent sheltered among vegetation. Small-sized to medium-sized fish (7-10 cm) are solitary and patrol feeding territories (3-4 square m.) in a way similar to that reported for the scale-eating Catoprion mento. Stalking with some use of plant cover is a frequent mode of hunting employed by S. marginatus. It approaches its prey with a slow, stealthy movement from behind or below. It strikes its prey on the tail or anal fin, of which a piece is clipped out with a jerking motion of the body. This clipping is audible underwater. Lurking is also employed during daytime. |
| Water it lives in | Freshwater. |
| Climate | Tropical climate. |
| Wild diet | Hunting macrofauna (predator). |
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 90°F (up to 93°F in the hottest sampled areas) |
| Cool-season lows | about 55°F (down to 48°F in the coldest sampled areas) |
| Average temperature | 69–79°F across sampled records |
| Relative humidity | 71–75% on average (driest month about 64%) |
| Rainfall | about 1358 mm a year |
Measured at 162 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.
| 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 |
| Appearance and size | Maximum length 27.1 cm tl male/unsexed; maximum published weight 440.00 g. — FishBase |
| Biology | Feeds mainly during the daytime, though some large fish (15-20 cm SL) extend their foraging activity to dusk (about 1800-1900H). Night is spent sheltered among vegetation. Small-sized to medium-sized fish (7-10 cm) are solitary and patrol feeding territories (3-4 square m.) in a way similar to that reported for the scale-eating Catoprion mento. — FishBase |
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 total length. Fish in home aquariums often stay smaller than wild records.
Water temperature
Range the species tolerates; aim for the middle.
Water hardness
Minimum tank footprint
Seriously Fish recommends a tank base of at least 47 × 15 in (about 46 US gallons).
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.
