Breeding Red-belly Piranhas
by Wayne Mah
If you have a group of adult red Piranhas, Serrasalmus nattereri, and they are larger than 6 inches, you maybe lucky enough to someday have two of them pair off and start mating. Your aquarium should be atleast 100 gallons, the water and the group of Piranhas should be well established, i.e, more than 6 months together. There should be no overcrowding so maybe a group of 5-6 piranhas. Try to pick healthy thick and thin adult Piranhas. Thick red piranhas in most cases represent females and thinner red Piranhas represent males. In all my piranha breeding experience, this sexing of the piranhas seems to be very accurate. But make sure you are not looking at them after they have fed or else the body will have been distorted. It is a very subtle difference but to a trained eye it is easy to detect. Having found males and females does not guarantee success, it only improves the chance. Telltale signs of possible success!
When two of your Piranhas begin to pair off and move away from the rest of the group, the mating ritual has begun. Both the male and female will stake out a territory and defend it throughout the mating process. Sometimes the female will wander away, but the male will seek her out and prod her back by bumping her or leading her back to their choosen spot. It is important that in your aquarium, there be area large enough for them to both circle around comfortably together. Another excellent sign of mating is when the male starts going around in circles in one area just above the bottom of the aquarium. The male may do this continuously for several days. The female is usually close by and both piranhas will chase away any other piranha that may come close. Before mating, the two pairs of piranha will likely eat quite a bit more than what is normal. But during mating and lasting for a few days, the two Piranhas may not eat much at all. Also during mating, there may be quite a few battle scars on all the piranhas in the aquarium as the pair defends their territory with a parental tenacity unseen at other times. During actual mating, both piranhas will point their faces towards the bottom of the aquarium pushing/gyrating their bodies together and all the while blowing their mouths at the gravel beneath them. Once the mating is over, the male remains with the eggs, while the female will have joined back up with the rest of the group. the male will continue to circle the area where the eggs were laid, thus fanning the area with new oygenated water. if you are lucky to have reached this stage, you should prepare a 10 to 15 gallon tank with heater and undergravel filter only. Use water from you main fish tank where the mating piranhas are and start waiting for signs the eggs hatching. The moment you spot any fry swimming, immediately siphon as careful as you can the area where the eggs where laid. Be wary the male will attack trying to protect the eggs. You can try to remove him before siphoning the eggs. Make sure you do not siphon before you see the fry swimming or else the eggs may not be ready. Once the eggs and some fry are in the smaller tank, start producing for daily consumption, live baby brine shrimp. (A good pet shop will show you how that is done). The fry will only eat this so you have to know how to make some.
It is my understanding that slightly warmer temperatures than normal, say 82 degrees and live feeder fish are very helpful in producing a mating pair. For my experience, it has been pure luck because i have done nothing out of the ordinary to have my piranhas breed and moreover, I have had several different pairs breed at different times and in different aquariums. It must be the tap water with some hidden love potion!
YORK UNIVERSITY, 4700 KEELE ST.
NORTH YORK ONTARIO. M3J 1P3