Too many possibilities for us to speculate I reckon.. Like you mentioned, maybe they got really lucky with a pair that didn't rip each other to shreds? They must have a hell of an eye for sexing arowanas, 'cos I'm not even sure if there are any visible differences between male and female (to my knowledge).. Or, maybe they bought a pair from a breeder? Probably very unlikely, but some people might have means..? People in Asia with big ponds in their backyards probably have the best chance of identifying a pair from juveniles and then removing them to a living room tank to spawn I reckon. But then again, a living room is probably not the best place for a spawning. There's a youtube video in Thailand I think where they have a hidden camera inside the tank and it's really dark because it's a concrete pond, so it always seemed to me that arowanas preferred privacy during their spawning, but I dunno, maybe living rooms work just as well? :dunno: