Piranhas are unique creatures that have gained popularity not just because of their appearance, but also due to the many myths that are told about them. Unfortunately only a few species of piranha have been bred, including Serrasalmus nattereri, S. spilopleura, S. gibbus, S. rhombeus. Another that is considered relatively easy to breed is S. maculatus.

Whichever of these species you choose, you should have an aquarium of at least 100 gallons. A group of 5-6 piranhas is quite appropriate; however if you want them breeding it is best to keep a pair only, so that there are no other fish to bother them. To find a mating pair select two adult piranhas, one thick and the other thinner - in most cases thick piranhas represent females and thinner piranhas represent males. Just make sure you are not looking at them after they have been fed. Although having found a male and a female doesn't automatically mean success, it is a step on the way.

The ideal temperature is between 73-83F. Standard fluorescent bulbs are fine for the lighting. Piranhas also like some protective cover, and you should also make the lighting of half of the aquarium darker than the other. Piranhas are hardy fish but it is a good idea to maintain the water clean and clear. In their original Amazon River habitat, the rainy season is when most fish spawn. Frequent and bigger water changes seem to have an immense effect on the success of breeding (as they simulate the rainy season) and are most helpful in getting the piranhas into breeding condition.

When your piranhas lose all their colour and turn almost completely black, they are in breeding condition! Both of them may start to protect a certain spot; chasing off other piranhas that come too close. When they start picking up gravel in their mouths as if digging, it usually means they have already begun the mating process. Be careful not to disturb your piranhas during this time! The female will release eggs into the pit, and then leave the nest (but might stay close by it). The male is usually responsible for guarding the nest and eggs. The number of eggs laid varies from 700-4000. The eggs hatch in 2-3 days.

If you are lucky enough to have reached this stage, then it's time to take care of the fry. Prepare a 10 to 15 gallon tank with heater and undergravel filter. Water should be from the parents' tank. Be very, very careful when transferring the fry, as the parents can be extremely protective and aggressive. The fry will quickly absorb their yolk sacs and you can start feeding them live baby brine shrimp as food.

One thing you should be aware of is the legal issues. Some states do not allow the sell or ownership of piranhas at all. Other states require that you obtain a permit to sell or own a piranha. Be sure to check to see if any local restrictions apply before purchasing your piranhas.