question about black piranhas

[phantoms]

for those that have these, do they do better as a single fish or as a group? i know they get huge. are they easy to breed? can you tell male and females apart? reason i am asking is that i have a 120 gallon tank all set up with snothing in it (my alligator gar jumped out and didnt make it ). im looking at another gar, maybe a wolffish, or perhaps a black piranha ( or few). i know the gar will out grow the tank, so perhaps a piranha or wolffish would be better suited for a 120. thanks for your help

 

[_Sushi_]

Black piranhas (Serrasalmus Rhombeus) can only be kept as a single specimen in the home aquarium. They can reach at least 15" (although it's unlikely in a tank) and take a LOONG time getting there!

As for telling genders, the only way you can really tell, is if you get {VERY} lucky like Demjor19 and Karajo and your Rhom decides to lay eggs! It takes a lot of hard work, and great care to get them to that point, as they have to be extra happy and healthy to do so.

Also, Kingofkings has a fine example of the species. If you can, I would suggest hunting down pictures of his monster as well as Demjor's.

If you have the patience, I would suggest growing them out from a baby, nothing is better than looking at a massive and impressive animal and saying "I raised that myself!!" If not, they are available at larger sizes, such as 10+ inches in length...they get pricier as you go up.

If you want a group of piranhas, your best best is one of the Pygocentrus species, Nattereri* (Redbelly piranha, or RBP), Cariba (Caribe) or Piraya.

*an extra big thanks again to oddball for correcting the spelling of the RBP species name!

 

[Tango374]

The largest of the serrasalmus group is the Rhombeus. Which is known as the "black piranha". Be careful though, there is a dozen of so fish in the serras and alot of pet shops have no idea how to identify young serras so they just put the common name on them as a black. Rhoms get the largest by far...in the wild around 20" but smaller in captivity (around 14" if your lucky) if grown from juveniles. Compresses and sanchezi which are very commonly sold as blacks only grow about half the size of a rhom and do not require anything near a 120 gal.
I recommend that if you have the money, to buy from a good piranha dealer and to buy an adult rhombeus 14"+. Rhoms are very slow growers reaching 6" in the first year and slowing way down to .5"-1" per year from there. A 120 with one 5" rhombeus will get old for most keepers real quick (as I write this I'm currently setting up a 72x18 hundred gallon tank for my 5" rhom. lol. I said most).
One Rhom is all you can have for they are solitary fish and will not tolerate tank mates. As they grow older to large adults you can have small schooling fish's.
Rhoms have never been bred by the average hobbiest. I want to say they have only been successfully bred in capivity once in a large public aquarium.
They are awsome fish. Sometimes very shy when young but usually come out of they're shell with time and become almost dog-like. Very different from the average red-belly.

 

[BigShawn]

Well those are the best two answers that one could give............

 

[StIcKy~RiCe]

Rhomb are NOT the biggest piranha...Serrasalmus Manny are.

 

[phantoms]

ok, so raising up a small group of rhomb is out of the question in a 120? when i say that, i only want to grow a few up in order to get a pair. or is housing 2 rhombs just not feasible since they will attack each other? the little ones will kill each other? i dont want a school of adults, just trying to raise up a pair. would be cool to try and get them to breed down the road. sexing them is only when you see one lay eggs? there isnt any other tells that let you tell them apart?

 

[_Sushi_]

No, unfortunately in anything less (according to www.OPEFE.com) than 500 gallons, Rhoms can only be kept singly. Which really stinks, but, there's not a whole lot you can do about it!!

When you have a breeding pair, the female will be thicker around the middle, and that's really about it. And even then, what you think might be a female, could just be a male who needs to lay off the feedbag a wee bit.

you could try seperating with a partition, but make sure it's VERY sturdy, or you'll have problems when they're bigger. And see what happens then, if they lay eggs or whatnot, but it'd be a lot of risk, with $40+ fish.

 

[phantoms]

aight. thanks you guys

 

[Tango374]

Rhomb are NOT the biggest piranha...Serrasalmus Manny are.

Serrasalmus Manueli is listed under OPEFE of obtaining a total length of 43.5cm (17.1") and then claims that it probably grows larger. S. Rhombeus measuring 19" TL is no where near being a myth or a probably and are out there. Specimens surpassing 20" is even a good possibility. The myth is a 2 footer. Show me evidence of a Manuel's piranha bigger then 20". Until then, Serrasalmus Rhombeus is the top dog.

 

[vinizuh]

Serrasalmus Manueli is listed under OPEFE of obtaining a total length of 43.5cm (17.1") and then claims that it probably grows larger. S. Rhombeus measuring 19" TL is no where near being a myth or a probably and are out there. Specimens surpassing 20" is even a good possibility. The myth is a 2 footer. Show me evidence of a Manuel's piranha bigger then 20". Until then, Serrasalmus Rhombeus is the top dog.

http://www.piranha-info.com/default.php?lang=en&id=s_manueli
theres a 20" manny, which shows the potential. so i wouldn't call s. rhombeus top dog. Pygocentrus Piraya can also reach 20" and probably more.