You need to remember some things like
Do not ever keep your aquarium open. Arowana's can jump out of the aquarium anytime. My Arowana did that twice. Even while changing your water you have to take care of that.
Arowana needs more of insects, shrimp etc. more of nonveg food.
do not keep small fishes with aro less than half of your Arowana they are likely to be eaten by your aro.