Asian/Jardini arowana have a more pronounced tail fin structure, and hail from the coasts of china/asia. Where as the black and silver are from a different geography (amazon/SA) and feature a "pointed" tail fin structure. The Jardini is considered more agressive than the black/silver aro's. Asian and Jardini are the same fish, silver and black are color morphs of the same fish.
Okay sir you obviously have no idea what you're talking about. Master Arowana, i suggest you disregard this entirely.
Fishbase is an excellent scientific site on the various species, it will give you all the identifying information you need.
Also feel free to post a photo of the arowana in question and we can identify it for you
T
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