Red bellied piranha in the aquarium

Red bellied piranha in the aquarium

Setting up a fish tank for piranhas sounds impressive. More and more fish keepers decide to have red bellied piranhas in their own aquariums. However, they are often not aware about many facts that are key for their (both fish and human) happy life.

red belly piranha

General characteristics

The latin name of red- bellied piranha is Pygocentrus Nattereri. The red-bellied piranha's natural habitat is Amazon river basin and many natural reservoirs of North Eastern coast of Brazil. This freshwater fish is considered as the most dangerous predator in these waters. Red bellied piranhas are shoaling fish and when they hunt- they do it together, lacerating the victim's body piece by piece. In natural habitat, piranhas eat only meaty foods such as other freshwater fish or small aquatic invertebrates.

How to set up a piranha fish tank?

Below you will find information how to choose the proper tank size, equipment and what diet should be provided for happy red bellied piranhas life.


Generally, first we recommend to think twice if we really want to have piranhas at home. Be aware that these predators are big and live long. Moreover, which is obvious, they are aggressive fish so if you will want to have some peaceful species soon, you'll probably need to set up a new fish tank (if you have space and money). Another thing is their diet which is surely more expensive than fish flakes for tetras. The long lifespan means that even if you want to give away the adult fish, many fish keepers won't adopt it (or rather them because they should live in herd as mentioned above).

Tank size

Red piranhas belong rather to larger fish species, therefore the tank size should be properly chosen. Although for a group of small individuals a tank of capacity of 53 gallons should be sufficient, when they grow up, it will not. For a group of 5-7 adult piranhas the minimum tank's capacity should be 265 gallons and it should be at least 79 inch long.


For substrate fine gravel or sand is perfect. This is because in wild female fish lays eggs in the pits which they dig instinctively. Therefore it's good to choose solid aquatic plants that can be sticked to the hardscape above the substrate. In this case, having floating water plants is super. They absorb contamination present in the tank, improving the tank water quality which is rather difficult to control without sufficient filtrations system. Moreover, they provide dim lighting. This is important because wild piranhas live in black waters of South America. Bright lighting makes them skittish. Also remember to create hiding places in the form of rocks and wood. And last but not least, if you want to keep red piranhas, the aquarium cover is necessary as they like to jump out of the aquarium.

Water parameters & equipment

Usually we don't match these two areas together, however understanding red piranhas behavior is key here. Although they have good metabolism, piranha fish are very messy eaters so the contamination in aquarium water can be high. Excrement and food remains are the source of nitrates harmful for fish. Therefore, the tank should be equipped with powerful external filter and plants supporting its work. Moreover, the water changes should be frequent and generous. Ph should be between 6.5 and 7.8, alkalinity between 3 ° and 8 ° (50 ppm to 140 ppm), and temperature between 75 ° and 80 ° F.

Cast in the piranha tank

Red belly piranha is an aggressive fish therefore it's recommended not to introduce other species to the tank. Even in this situation, piranhas need to be fed generously. Otherwise, the may show up cannibalism among the herd. Some experienced piranha breeders keep them together with other larger fish species such as armored catfish. Although these tank mates may get along for some time and live together in harmony, it is rather temporary and later or sooner will be eaten by red belly piranhas.


Red bellied Piranhas Piranhas are best fed with dead fish and other meaty foods. Despite the fairly common, the use of live feeder fish is not advised and aquarium trade leaders will all explain that ornamental fish used for this purpose (goldfish, guppies etc) carry parasites that can harm the red belly piranhas. For this reason, only preprepared fresh or frozen meats are advised. Young Piranhas should be encouraged to take as many different kinds of food as possible to allow the fish keeper to be able to offer a balanced diet of fresh freeze-dried foods along with dried appropriate pellet food. To tempt and encourage your piranha to try new foods, the food can be moved (using tongs, not hands!) to replicate live animals and stimulate the hunting instincts of the fish. This applies to many red belly piranhas that are not yet used to the conditions in the aquarium.

Red belly piranhas can be fed chicken or beef. However, this is not fully recommended as mammalian meat may contain fats that fish cannot digest. Over time, this can cause serious health problems. For the best piranha care, a varied diet is recommended as well as food that they can eat within a few minutes. It is best to remove uneaten parts from the tank immediately to avoid affecting the water quality.


Breeding most piranha species at home is difficult, but not impossible. For this purpose, it is best to buy a group of about 6 piranhas, from which, with a bit of luck, a pair will form. During the spawning season, the male fish digs holes in the substrate where the female lays about 300-400 transparent, yellowish eggs. The eggs hatch in 3-5 days. Then the larvae are best transferred to a separate container, e.g. using a sucker. After 7 days, the fry will be free swimming. At first, they are fed brine shrimp larvae, then chopped tubules and zooplankton. When the fish reach a length of 1.5-2 cm, they begin to attack each other. This can be avoided by separating them by size and feeding them well.


If you decide to have the red bellied piranha in your fish tank, you need to be aware that their diet should be various and they should be fed generously. The tank should be equipped with good filtration system and conditions reflecting the wild habitat. These predators are long living and grow up quite big so think twice if you are ready for this challenge.