How big of a tank do you need?

[Otherone]

If your looking for more than 1 Piranha your basically looking at the 3 Pygocentrus species - Cariba, Nettereri, Piraya. Shoal rule of thumb - 20 to 30 gal of water per Piranha. Piraya's get 10"+ so the wider the tank the better. The other 2 species can get 10" or more however it takes a decade or so and most don't. 8-9" is a healthy adult size for RBP's and Cariba's.
Another shot in the dark is Serrasalmus Maculatus they might shoal they might not.
Most of the Serrasalmus species do best solitary. Serra's range from 7" -16" and the shoal rule for Pygo's doesn't apply - Tank sizes can range from 55gal. for Sanchezi to 120+ for a single Rhombeus. Do a little research - pick your species and this will dictate your tank size.

 

[STXman]

ya i need this pages info too thanks haha

 

[Zander_The_RBP]

If your looking for more than 1 Piranha your basically looking at the 3 Pygocentrus species - Cariba, Nettereri, Piraya. Shoal rule of thumb - 20 to 30 gal of water per Piranha. Piraya's get 10"+ so the wider the tank the better. The other 2 species can get 10" or more however it takes a decade or so and most don't. 8-9" is a healthy adult size for RBP's and Cariba's.
Another shot in the dark is Serrasalmus Maculatus they might shoal they might not.
Most of the Serrasalmus species do best solitary. Serra's range from 7" -16" and the shoal rule for Pygo's doesn't apply - Tank sizes can range from 55gal. for Sanchezi to 120+ for a single Rhombeus. Do a little research - pick your species and this will dictate your tank size.

that's not entirely true. i have heard of rbp's being larger than 9 inches after only a few years (2-3) of years pirayas get to atleast 14 inches in probably about 3 years. everything else is exactly right though.

@dannyboiiii


LMAO okay explain this i had 8 piranhas that killed off 2 other piranhas what am i left with ? 6. What is six ? An even number.

if were going to base actual fish keeping guidelines off your single biased experience we might as well base them off my single biased experience as well.


@ OP

never keep 2 together it usualy isn't a good idea the dominant one ends up beating up or killing the less dominant one with a group (of 3 or more) the agression is more spread out.

IMO 75 gallon tank for 3 or a 40 gallon breeder for 1