Name: Pygocentrus nattereri
Origin: Guiana to La Plata
I love these fish. I have had the same one I have now for 11 years. Every two weeks he gets 8 goldfish to eat with an occasional pork chop! Whenever I give him goldfish he chomps right through the bag and eats them.
Piranha are not at all the vicious fish they've been made out to be. It's unfortunate that people think they'll kill anything in the water because many people will starve piranha in the home aquarium to see them go into a furious feeding frenzy. In reality, piranha are more of a parasite than a predator. They don't usually kill the animal they eat - they mainly take a bit of a fish's scales or its fin. In South America piranha are often trapped in small pools of water during the dry season. Cattle ranchers whose livestock need the water for drinking sometimes stock the pools with peacock bass to kill the piranha. People swim in water that have plenty of piranha in them all the time, and are not frequently attacked. If you're going to get piranha for a home aquarium, make sure you have a tank large enough to house at least half a dozen of the fish together. Any more than that, and they'll pick on each other too much. More fish give them the chance to diffuse their aggression.
Basically, after years of keeping and breeding Piranhas I would advise as follows:
1. Respect your fish at all times - this means in two ways; Firstly, the potential power of the fish and their ability to use their teeth in lightning fast bites. Secondly - respect your fish's nervous disposition and personal space. Piranhas can be extremely shy and nervous fish. Mixed with a primitive response mechanism and you end up with a fish that will attack when it is frightened. So give it some space, do not move things in the aquarium close to it and do not make them jump.
2. Try and live by this rule - feed first - then work on aquarium. Its sounds simple doesn't it... but people have kept piranhas and placed their hands in the tank when the fish have not been fed for two days. The fish may not see the hand as direct food, but they have enough intelligence to associate the hand and the owner's presence with feeding. My friend did this once with a single black piranha... he ended up with a chunk out of his thumb and a few stiches to keep it attached to his hand. So feed him first, watch him feed and then after about 10 or 15 mins when that "After Sunday Lunch" feeling has settled in the fish - do the work. Very often, your piranha may be so shy that they won't eat in front of you! Seriously, he may wait until you are out of sight before eating... it has happend to me on several occasions.
3. Invest in a pair of tongs - especially for the aquarium. they have a grip handle and a trigger that will open the claws on the other end. I never ever put my hands in one of my piranha tanks if I can possibly use tongs to do the job.
4. Watch your fish - make sure that they are well away from you. Although a full grown piranha can hurtle across a tank at alarming speed.
5. Try and get a divider fitted that simply drops in from above and isolates the side of the aquarium you want to work on.
6. During heavy maintenance work and tidying up you may find it easier to siphon off some tank water into a bucket with a lid, catch the fish in a long net and transfer him. I know that people would say that this causes stress... but so does a missing finger on your hand. Piranhas endure far worse in the drying pools of South America... a plastic net and bucket are heaven when compared to this. Note... make sure your net is tough enough, they will eventually wear out.
Generally, don't put your hands in if you can help it, never before feeding and try and isolate the fish whenever possible.
I am suggesting the use of plant-based foods for feeding purposes. I've had success feeding my piranhas green beans and romaine lettuce. This seems to have eased their temperament quite a bit. It is also a cheap food source (we all know that food can get quite expensive!). If they don't eat it right away, just fast them for a few days. They'll at least try it. Another inexpensive food is uncooked, unpeeled frozen shrimp. You can usually get two pounds for eight bucks. Make sure you thaw the shrimp, and then peel them. Peeling and de-veining will help keep pollution minimal.
I totally agree with what everyone has written here about piranha. I've raised more than a few eyebrows when telling people I thought the little guys were cute little critters that just happen to have teeth. They were the easiest fish to maintain. Simply toss in a few feeder fish and the piranhas were good for a few days.
The cutest thing they did was right after I brought them home from the fish store. They laid there, flat as pancakes, in the bag, still as dead fish. Upset, I called the immediately called the store and told them they had sold me extremely sick fish. The clerk told me piranha "play dead" when frightened. That I should transition them to their tank and wait. After a little while, they'd come to and swim around...which they did.
The scariest thing I had to do with one piranha was hold it in one hand and use my other hand to remove a large piece of gravel that had gotten lodged in one of its eye sockets.
Never before had I fish that I loved and respected at the same time!
I have had my red belly for 4 and a half years. And we've been through moving tanks and all sorts of stuff. And I agree with the person who said they are the easiest fish to maintain. They're hardy fish and can endure water changes very well and mine hardly ever got sick. Except for two cases of popeye in 4 years. He never had ick, or any other illness. But I can't keep nothing in there with him, not even a pleco, but it doesn't bother me. He's been alive for four years he deserves his own tank.