Well, you will definately have a beutiful community tank.
Here are some rules of thumb for those who are inspired.
To set up an aro com tankis a difficult task because if done wrongly you with get dead arowanas!
Rules to setting up aro com tank
1. All arowanas has to be of the same size. This rule cannot be bended.
2. Big tank is necessary. Since it is impossible to create hiding places for them, in a confrontation, the weaker aro needs to have space to evade attacks. They don't need a football field of space to outrun one another since arowanas don't chase for long distances (They're not like cats!) . But they need the space to perform 'sidesteps', during mini confrontations.
3. The more fish the better. When in big numbers, aggression is spreaded out and a fish that loses a confrontation can 'disappear' behind the other fishes with a quick turning.
4. All the arowanas must be introduced to the tank at the same time.