I am sorry for your lose...but I have to agree with the others, by the looks of it your tank isnt even twice his body length...if the tank is too small Arowanas feel insecure and are more prone to jumping and they need a larger tank.
Well there is a saying with arowanas. It may have taken ur bad luck with it and kept u and ur family safe on ur trip. Ahahahah it's a Chinese saying i have heard lol.