So, will Piranhas eat bones? In short, no, Piranhas will not eat bones but the question requires some nuances. While possessing a bite that can go through bones, especially of small rodents and reptiles, the Piranha are after the flesh on the bone, not the bone itself.

True Piranhas The largest true piranha is the San Francisco piranha (Pygocentrus piraya), also known as the black piranha or black-tailed piranha. Native to the Sao Francisco River basin in Brazil, this aggressive omnivore grows to more than 13 inches long and weighs up to 7 pounds.

Piranhas commonly grow to 12 inches in length and weigh less than two pounds, but have been reported to grow up to 16 inches and over 7 pounds.

For this reason, the number of Red-Bellied Piranha is always meant to be around 3 to 4 fish, no matter what the size of the aquarium. However, each fish should be given approximately 20 gallons of its own space. Thus, up to 4 Red-Bellied Piranha are thought to be good for a 75 gallon tank.

It is LEGAL to own piranhas in some states including Michigan, New Hampshire, Delaware, Illinois, Indiana, Iowa, Kansas, Maryland, Minnesota, Missouri, Montana, Nebraska, New Jersey, North and South Dakota, Oregon, Pennsylvania, Rhode Island, Tennessee, Vermont, West Virginia, Wyoming and Wisconsin.

How Much Do Piranhas Cost? The average cost of 2- 2.5” Piranhas is around $30. Experts suggest that this is the ideal size of Piranhas to introduced into an aquarium. Piranhas species smaller than 2” can cost between $5 and $15.

As they reach more adult stages, and their growth slows you can feed them once a day. There are no hard and fast rules, but if you drop feed into the tank and put in as much as they can consume in 3 minutes or so, you should help your Piranha keep healthy.