Above: In this picture a young Premium Red Belly Pacu is swimming in one of our aquariums, when one of us snapped this picture.

Comments: These are awesome looking fish that get big, very big, very very big.

Origin: The ancestors of Red Belly Pacus lived in the Amazon River. But now they live in aquariums all over the world.

Maximum Size: they can grow to be more than 30" long, which is too big for almost all aquariums.

Many aquarists have raised a Pacu to 8" or 12" or even 16" before deciding to give it to someone else.

The problem is: there usually is no one else. Even the biggest public aquariums have all the Pacus that they want.

Behaviors: Red Belly Pacus are usually not aggressive, but they can eat smaller tankmates, so be careful when choosing tankmates.

Compatibility: Some recommended tank mates include, Arowanas, Pictus Catfish, and Plecostomus.

Click here to read more about compatible groups of pet fish.

Temperature: Red Belly Pacus live best from about 75 to 80-degrees F. with 78 being perhaps ideal.

Click here to learn about aquarium temperature, aquarium thermometers, and aquarium heaters.

Feeding: Premium Fish Food Pellets is the best food for these fish to eat.

It is best to feed them small pellets when they are young, then gradually increase the size of the pellets as they grow.

In their natural habitat Pacus eat seeds, nuts, and fruits that drop into the water.

Click here to learn more about and shop online for premium fish foods.

Water Conditions: These fish can adapt to most types of water, and so as usual it's best not to try to change the pH or alkalinity of your aquarium water.

Click here for a lot more information about aquarium water conditions.

Aquarium Size: when young, a few a Pacus can live in a 30-gallon aquarium, but very soon they'll need a bigger aquarium, and then an even bigger aquarium.

Eventually one Pacu will need an aquarium with more than 1000-gallons of water.

Decor: Red Belly Pacus do not need gravel and a layer more 1/4" thick will usually fill with bits of uneaten food that will contaminate the water.

Click here for more about aquarium gravel.

Live plants are beautiful and improve the water quality, but Pacus are ravenous vegetarians that will immediately eat most plants.

Aquarium Filter: Bio-Wheel Filters are highly recommended.

Most 30-gallon aquariums have room along the back for a Penguin 350B Filter, and this is sort of the minimum set up for a few small Red Belly Pacus.

Better is a 120, 150, or 200-gallon aquarium with as many Penguin 350B Filters as will fit across the back.

Click here to learn more about aquarium filters.

The addition of Lava Rocks will keep nitrates in the ideal range.

Click here to learn more about using Lava Rocks in aquariums.

Life Span: Red Belly Pacus can live for several years.

In a huge aquarium with excellent water conditions and fed premium foods including lots of vegetables and fruit, they'll most likely live for many years.

Gender: It's nearly impossible to tell males from females just by looking at them. During breeding, it may be easier to determine their gender.

Breeding: Red Belly Pacus are egg layers, it is not common for them to breed in captivity but only in huge aquariums or vats.

Click here for a lot more about breeding various tropical fish in aquariums.

Popularity: The Red Belly Pacu has been a very popular aquarium fish.

Names: Their scientific name is Colossoma brachypomum.

Variations: There is now an Albino Pacu available as an aquarium fish.

We hope you've enjoyed reading these comments.

DrT - 12/27/2014