Red Belly Piranha Question

[steve]

I had 4 Red Bellies but due to cannibalism i now have one 5 inch in a 55 gallon tank. He is pretty nervous dashing wildly when you catch him off guard. I was wondering if anyone has experience with piranhas and could tell me how to help him relax. I know that he would be calmer with more piranhas around but I was told that once by themselves for too long they cannot be placed with others because they will want to fight. Any help appreciated.

[Fishfirst]

Two words, MORE COVER, and this may not even help solve your problem. You can get away with adding more piranha though, you just need to make the tank look different first (by rearranging and get piranha the same size. Cannibalism is usually a spatial issue or a food issue... what are you feeding and how often? I've got 3 in a 55 that are great with eachother.

[fish_doc]

Piranha, silver dollars, and pacus love cover as has been stated. They are prone to being skittish when sudden tank lights are turned on or off or People get near the tank to quickly. And its true dont keep him alone to long otherwise there is no placing him back in a group. They do best in larger groups but dont overcrowd the tank. Small numbers are best avoided.

[steve]

I feed him silver sides or frozen krill once every 2 days, i fed them once a day when they were together but they were in a smaller tank. Due to this they killed each other, the one i have now has been by himself for about 8 months. I want 2 more piranhas and the pet store has 6 almost the size of mine, but they look unhealthy kind of like this picture i saw of a fish with tuberculosis. but they might have been fed too much aswell. I am going to add more live plants but i dont want the roots to interfere with my undergravel filter. I dont want to euthanize him in order to have a school of piranhas.

[Fishfirst]

He should get a meal a day... and I would vary up his diet... other good things to give him are, Shrimp (brings out his color) Catfish, Walleye, Pollock, and Squid. 8 months is a long time by yourself, he might be able to go in with a school of p's that are larger than him though. Don't euthanize your fish, for a larger piranha is fairly valuable. I'd sell him if it came down to it.

[steve]

BTW- How much current is too much? I have 1 Emperor 400 Bio-Wheel Filter and 2 30 gallon powerheads pumping 175 gph each. The top of the water is moving quite a bit, but when he swims by the powerhead he seems to like the flowing water. I was also wondering if i could add 1 more RBP thats his size, would they fight or do i need a odd number of P's like 3? Thnx

[Fishfirst]

Piranhas are river fish, they live in the amazon and are often like a good current in aquariums (it makes them more active). If you add one more they will most likely tear eachother apart... if you add two the aggression will spread between themselves and in theory you will have less of a concentration of aggression on just one fish. As always there is a risk involved when adding new piranha... but guys on piranha-fury.com have done it. Make sure they get two small meals a day so they don't start to canniblize. Usually aggression (nipped fins, a nick here or there) is completely different than out right eating eachother.

[steve]

ok thanks