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No federal permit to keepSheep-pacu
Acnodon normani
Fishes › Tetras, piranhas and pacus (Characiformes) › Serrasalmidae (Piranhas and pacus)
Acnodon normani, the sheep-pacu, is a species of freshwater ray-finned fish belonging to the family Serrasalmidae, which includes the pacus and piranhas.
Care at a glance
Species-specific aquarium care
- Tank: At least 36 in long and 15 in front to back for one adult (adults commonly reach about 7.8 in / 19.9 cm).
- Water: Freshwater.
- Temperature: 72–82°F (range recorded for this species).
- pH: 5.8–7.2.
- Hardness: 0–18 dGH.
- Layout: Uses both the bottom and open water: give open swimming space plus cover near the substrate.
- Diet: FishBase classes it as a omnivore.
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 59 × 18 in (roughly 80 US gallons); space needed is rated “very large tank”.
- Water: a fairly wide range, from slightly acidic to slightly alkaline, 72–82 °F, pH 5.5–7.5, 2–15 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: “Relatively unfussy, although some cover and well-oxygenated water with a degree of flow should be provided.”
- Diet: “Often said to be a frugivore or generalised herbivore, although aquarium observations suggest it may also feed on the scales of other fishes to an extent.”
- Tankmates: “Given its propensity to pick at the scales of larger fishes, this species is not recommended for the community aquarium, although it does not seem to target much smaller species.”
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
This species is found in the Amazon River basin of Brazil.
Quoted from the Wikipedia article “Acnodon normani” (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. Uses both the bottom and open water. |
| Water it lives in | Freshwater, 72–82 °F (22–28 °C), pH 5.8–7.2, hardness 18 dH. |
| Climate | Tropical climate. |
| Wild diet | Troph of juv./adults from 1 study. |
What this means for care
- Keep water within its wild range, 72–82 °F.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 91°F (up to 93°F in the hottest sampled areas) |
| Cool-season lows | about 67°F (down to 60°F in the coldest sampled areas) |
| Average temperature | 77–79°F across sampled records |
| Relative humidity | 79–83% on average (driest month about 75%) |
| Rainfall | about 1918 mm a year |
Measured at 39 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 | Acnodon normani, the sheep-pacu, is a species of freshwater ray-finned fish belonging to the family Serrasalmidae, which includes the pacus and piranhas. This species is found in the Amazon River basin of Brazil. — 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 |
| Appearance and size | Acnodon normani can be distinguished from A. oligacanthus in the possession odf a more acute snout and the lower jaw being shorter than the upper jaw. The premaxillary teeth of A. normani are very widely separated, to a greater extent than in any related species. This ish has silvery flanks with bluish stripes running down from the back to the lateral line. — Wikipedia (community-edited) |
| History and naming | Acnodon normani was first formally described in 1951 by the American ichthyologist William Alonzo Gosline with its type locality given as the Rio Santa Teresa, a western tributary of the upper Rio Tocantins in Goias State, Brazil. — Wikipedia (community-edited) |
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 in nature; aim for the middle.
Water hardness
Minimum tank footprint
Seriously Fish recommends a tank base of at least 59 × 18 in (about 80 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.
- Wikipedia (species article) Community referenceFree encyclopedia; useful overviews with their own citations. Intro text is quoted under CC BY-SA 4.0.
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