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.
I agree the tank was small. it was just a lil over tweice its lenght but not bigh enough. The bigger tank is in staging and almost done; had another week or so before I was to transfer them in to the 300G tank.