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No federal permit to keepUaru
Uaru amphiacanthoides
Fishes › Cichlids (Cichliformes) › Cichlidae (Cichlids)
Uaru amphiacanthoides, the uaru or triangle cichlid, is a species of cichlid native to South America where it occurs in clear streams of the Amazon Basin.

Care at a glance
Species-specific aquarium care
- Tank: At least 48 in long and 21 in front to back for one adult (adults commonly reach about 9.8 in / 25 cm).
- Water: Freshwater.
- Temperature: 79–82°F (range recorded for this species).
- pH: 5–7.
- Hardness: 5–12 dGH.
- 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.
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
- Water: soft, acidic water, 81–86 °F, pH 6–7.
- Difficulty: Difficult (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “A large roomy aquarium with a sand or gravel substrate and decorated with bogwood and roots is preferred.”
- Diet: “Stomach analyses of wild fish have revealed it to be an omnivore existing on a substantial amount of plant matter along with an assortment of invertebrates and even freshwater sponges.”
- Tankmates: “Suprisingly peaceful for such a large cichlid.”
- Breeding: “Wild caught Uaru will require water paramaters that mirror their natural habitat(very soft and acidic ).”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Central and South American cichlids
Applies to most species in this group. Habitat: Rivers and lakes of the Americas. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- Size ranges widely, from convicts at 5 in to Parachromis over 20 in; plan tank size for the adult fish.
- Most tolerate neutral, moderately hard water; strong filtration and rock or wood caves.
Climate & lighting
| Water | 75–82°F |
Diet
- Omnivorous cichlid pellets plus vegetables for herbivores (Vieja, Uaru) and meaty foods for predators (Parachromis).
Social life
- Territorial; breeding pairs can clear a whole tank.
Health watch
- Aggression and territorial injuries, especially when breeding; hole-in-the-head in poor water.
Understanding the animal
About this animal
About this animal
This species can reach a length of 25 centimetres (9.8 in) SL. It is also of importance as a food fish for native peoples and can be found in the aquarium trade.
Quoted from the Wikipedia article “Uaru amphiacanthoides” (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. Uses both the bottom and open water. Occurs in clear streams with a pH of 6.8. |
| Water it lives in | Freshwater, 79–82 °F (26–28 °C), pH 5–7, hardness 5–12 dH. |
| Climate | Tropical climate. |
| Wild diet | Hunting macrofauna (predator). |
| Behavior to plan for | Breeding: clutch tenders. |
What this means for care
- Keep water within its wild range, 79–82 °F.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 90°F (up to 92°F in the hottest sampled areas) |
| Cool-season lows | about 71°F (down to 69°F in the coldest sampled areas) |
| Average temperature | 79–81°F across sampled records |
| Relative humidity | 82–85% on average (driest month about 80%) |
| Rainfall | about 2366 mm a year |
Measured at 62 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 | Uaru amphiacanthoides, the uaru or triangle cichlid, is a species of cichlid native to South America where it occurs in clear streams of the Amazon Basin. This species can reach a length of 25 cm SL. It is also of importance as a food fish for native peoples and can be found in the aquarium trade. — 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 |
| Reproduction | Parents care for (up to 200) eggs and larvae. — FishBase |
| Biology | Occurs in clear streams with a pH of 6.8. Feeds on worms, crustaceans and insects, but needs plants as supplement. — 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.
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
Veterinary & husbandry research
Veterinary & husbandry research
- Capillaria pterophylli Heinze, 1933 (Nematoda: Capillariidae Railliet, 1915) in imported ornamental Cichlidae from Asia into South Africa: the first molecular data and scanning electron microscopy Molokomme PS et al., International journal for parasitology. Parasites and wildlife 2025
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.
- 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.

