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 6metres (18 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 tank mates for the Pacu fish species

You are in the thinkfish community creator for the Pacu fish species, you can learn all about how the tool works in assessing fish tank mate compatibility at the link provided or use the tool tips provided to guide you. Create a test fish community that includes the Pacu species and any other types of fish or crustacean you'd like to introduce - You can assess the best companions, tank size suitability, stocking levels based on filter type and volume and possible negative interactions and warnings as you build up your aquarium.

Please do check your water type for compatibility with your fish, which can be found on the Pacu information box above and your local water company providers website. Don't waste your money and endanger your fish!
Tank Details
question mark  Rename your tank:
question mark  Length: (cm)
question mark  Volume: (Litres)
question mark  Filter type:

* Recent changes to stocking & filter advice October 2018
* This fishtank will only last for this session - to save your tank please Join/Log in

question mark  Max Stocking level: 0cm
0-1 months 20%: 0cm
1-3 months 40%: 0cm
3-6 months 60%: 0cm
question mark  Current stock level: 0cm
Stock percentage: 0%
question mark  Suggested maximum
fish size for your tank:
My Fishtank Quantity Stock cm

There are currently no fish in your fish tank. To add fish, you can click the 'Add the Pacu to your tank' button. Or search for a different fish using the options presented above

sample fish tank
See an example tank as it would show on a user profile with enabled settings and community tanks.

To save your tank details in the Fish Community Creator you must be logged in CLICK HERE to login or create an account further down the page below

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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