Serrasalmus: Latin, serran, serranus, saw and a fish of genus Serranus + Latin, salmo = salmon
One of the few fish in the hobby which has a VERY SERIOUS BITE. Black piranhas are usually intolerant of all tank mates unless the aquarium is huge, they become increasingly handsome and aggressive with age. Ideally this species should be kept alone in its own tank. Unlike some other piranhas S. rhombeus doesn't form in to large permanent shoals and is more of a solitary fish in by nature.
Wild S. rhombeus prey on other fish for most of their diet when they are big enough, very small ones prey on insects. In captivity use earthworms, prawns, shell fish, and fresh or frozen whole fish such as lancefish, whitebait, sardines ect. Apart from the ethical issues in the UK it is illegal to use live fish or any other live vertebrate as food. Avoid using red meat apart from beef heart as it contains to much animal fat which fish cannot digest.
There are no external differences between the sexes. Neither parent guards the brood after spawning.
Black piranhas have been bred in captivity but not very often because of the difficulty in being able to maintain a pair in the same aquarium even for a short time.
S. rhombeus is a widespread species and not under any major threats. All specimens offered for sale will probably be wild caught, this is significant when it comes to their care because generally wild caught fish are less adaptable to changing conditions, poor water quality or the wrong water chemistry.
pH: 5 - 7
dGH: 3 - 10
Temperature: 22 - 28°C (72 - 82°F)
Size: 41cm (16in)
Min tank size: 675 litres
Difficulty level: Intermediate
Aquarium type: Specimen
Swimming level: Middle
Origin: South America: Amazon and Orinoco River basins, north and eastern Guiana Shield rivers, and northeastern Brazilian coastal rivers.
Habitat: Found in the rapids but is also captured in deep zones of main rivers
Species: S. rhombeus
Synonyms: Salmo rhombeus, Serrasalmus niger, Serrasalmo immaculatus, Serrasalmo paraense, Serrasalmus paraense, Serrasalmo humeralis gracilior, Serrasalmus boekeri, Serrasalmus normani, Pygocentrus normani