Name: Colossoma macropomum
Origin: Amazon Basin
My father-in-law and I bought two silver dollar size Red-bellied pacus and put them in his 200 liter tank. They would eat zucchini, lettuce and grapes from my hand, and they LOVE peas. When I would feed them worm cubes they would let me "pet" them, rubbing their dorsal fin. They would pick on each other a lot, and the smaller one's nose was all chewed up from the bigger one biting her in a lip-lock. They wouldn't kill any of the smaller fish in the tank with them, but they did eat the dead or sick fish. They grew to 33 cm before we put them in his 20,000 liter pond about two months ago. They are about 45 cm now and are living with Koi, large goldfish and a lot of mosquito fish. They still come up and eat out of my hand. We went and bought two more silver dollar sized Pacus about two weeks ago and they are already 8 cm. They do have small teeth and a powerful jaw, they eat Brazilian nuts in their native rivers along with any other fruit that falls from the trees. The natives spear and eat these fish for their "sweet" flavor; naturally sweet because of the fruit they eat. Remember that if your pacu attacks your other fish it's YOUR fault because you are the one training it to eat meat! We love Pacus and they are fun to watch, but they do grow extremely fast! If you have a small-medium tank and expect them to stay small, do not buy these fish. Everyone who has these fish can testify to that. You will need a LARGE tank! It is unfair to cram these animals into unsuitable environments, no matter how interesting they may be. It is rare that your average aquarist will have the means or even the desire to maintain this type of setup and commitment. Pacus also are very skittish and are labeled "TANKBUSTERS" for obvious reasons. They do jump out of the tank when scared. Sounds like a lot of work, but they are definitely worth it!
I bought two red belly pacus back in 1993, when they were only the size of a half dollar coin. Not doing any research on these two fish, I bought them because I enjoyed their manner in appearance, the way they fed, and their "unaggressiveness"; however, as they slowly grew in size, despite their small size, all of my small connunity fish became their dinner. Years later, (around Sept. 1999) reluctantly, I gave them up. They were still surviving in a 200 liter tank, with crystal clear water flowing endlessly, as they stayed by the bottom of the tank, moving slowly about, and only during feeding time did they briskly move their now 50 cm long, close to 6 kg bodies about. These two beautiful fish were like family members; the maintenance was grueling, but more importantly, I loved them, and could no longer subject them to such confining living space. Living only some 56 km southeast from San Francisco's famous Steinhart Aquarium, I finally got a commitment from the staff that they would keep my fish, instead of "utilizing them as fish feed". My pacus were initially placed in a 2000 liter holding/quarantine tank, making sure they did not harbour any parasites or diseases that could infect other members of the amazon-type setting they would eventually be placed. Finally, my two pacus were placed in a 50,000 liter amazon type pool, along with several larger pacus, caymen, large tortoises, eels, and other amazon type fish. On several occasions I visited them, and they grew even larger (twice their size). Interestingly, I was always able to recognize them (they were lighter in colour) and believe it, or not, I would gently tap on the glass, and "call" out to them: "Hey guys, how are you doing?", and as they had done hundreds of times when I had them at home with me, they would swim where I was, and stay by me, as if saying: "We are fine, now are you going to be feeding us?"
The Red Belly Pacu is a cousin to the Piranha, but generally lacks the aggressive quality. I myself thought this fish looked familiar...thus the resemblance to a Red Bellied Piranha. This fish can reach 60 cm or more and thus needs a huge tank. Some say 700 liters minimum. Usually this fish is kept in public aquariums. Why they are common in pet stores...who knows. They will make a mess of a tank if the tank is too small. They are very fast swimmers. The Red Pacu is actually smaller than the Black Pacus. It may fade in color as it ages. Pacus in the wild enjoy eating the fruits that fall off trees in the Amazon. They will eat a large variety of foods including grapes, peas, pellets, live foods, meaty foods, cherry tomatoes, plants, vegetable matter. Little is known about breeding this fish.
I have had 5 of the buggers and they are my most enjoyable fish to have raised. The pacu may eat anything it can get it's mouth around, but meat should never be a part of its diet. If you absoutely must feed it flesh, silversides, or other frozen fish should be used. Keep in mind also that these are opportunistic feeders and that their diet changes as they mature. Typical feeding behavior of these in the wild suggests that they are carnivores as juvenilles and herbivores as adults, providing that there are no plants for it to eat, the pacu will feed on it's tankmates if it goes hungry for periods of time. And yes it is true they are VERY powerful swimmers and they will break the glass walls of a tank if spooked! If you are just bound and determined you are not going to provide a big enough home for one, my advise is to use acrylic tanks, as acrylic is more durable.
We bought a baby red belly pacu about 2 years ago. He survived a red devil which killed all the other fish, including 2 oscars. Tried to kill our pacu, but he made it. Eventually the red devil died. Our pacu was the only one to make it out of 7 fish we had. We eventually got a white belly catfish and they got along great. Our pacu was about 33 cm long, he looked like a large dinner plate and weighed about 1 kg. He was beautiful. About a week ago he died. We were so upset. But we decided to replace him. We bought another one, about 16 cm and it's doing fine. I would highly recommend buying a pacu.
A fast growing fish. Eats everything: Brazil nuts, bananas, plants, bugs. Don't scare them, they can be a real tank buster. They get along with cichlids good, but need at least a 600 liter tank.