Pacu Tropical Fish Information

Colossoma macropomum
Behaviour Peaceful
Typical size 60cm
Max size 90cm
Tank Area Middle, all
Min Tank Size 250cm
Temp Min: 22℃ Max: 28℃
Feeding Pellets, wafers, vegetable based foods
pH Range 5.5-8.5
Hardness vs,s,m,h
Pacu Colossoma macropomum
  • Pacu Colossoma macropomum - thumbnail
  • Pacu Colossoma macropomum - thumbnail

Pacu (Colossoma macropomum)

Pacu Tropical Fish Learn all about the Pacu's feeding habits and food types, its behaviour, its origins, its natural habitats, is it male or female, breeding advice and information, suitable tank mates, its sizing and growth range, minimum tank size, water PH and more. Use our fish community creator tool to plan your tank set up and ensure that the Pacu is the right fish for your aquarium.

The Pacu will grow up to 90cm (three feet) in aquariums, and can get even bigger in the wild. Because of its size it should never be sold by any shop, nor bought by any fish keeper without an aquarium measuring at least 3metres (10 feet). Pacus are part of the same group of fish which includes silver dollars, red hooks, and pirahnas, although these are an exclusively vegetarian species. Despite their size, pacus are peaceful and can be kept with other large and well natured fish. Younger fish are timid so will need plenty of hiding spots, as well as vegetation to provide cover and food. Pacus are easy to care for and will adapt to different water conditions - providing you have a massive aquarium

This fish is excluded from the Compatibility Checker as it is unsuitable for community aquariums or may require expert care.

Pacu Facts

Family Characidae (Characins) | Synonyms Myletes macropomus, Myletes nigripinnis, Piaractus macropomus, Colossoma tombaqui, Colossoma oculus | Other names Black-finned Pacu, Black-finned Colossoma, Giant Pacu | Origin South America; Amazon | Natural Water Conditions pH 5-8, very soft to medium | Natural Habitat Open, vegetated waters | Sexing Anal and Dorsal fins are more pointed and may be bigger on males

Pacu Help and Advice

If you have a question about keeping Pacu's then please use our Pacu help forum. Join 100's of other fish enthusiasts with 1000's of years experience between them caring for and keeping fish like these.

Check Tankmates for the Pacu fish species

Create a test community that includes the Pacu fish species and other types you'd like to introduce - Assess tank size suitability based on filter type and volume, possible negative interactions and warnings.

Please check your water type for compatibility with your fish, which can be found on the Pacu information box.
Tank Details
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If you'd like to talk about the "Pacu" with our users, then we have a buzzing community of fish enthusiasts where you can talk about tank issues, Pacu fish behaviour, Pacu tank stocking and any other issues related to the Pacu fish or other types you may have.

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