So I cant have them together even though they r adult?
Jardinis are really aggressive, so most likely, every other fish in the tank will get killed off. This is as they grow bigger. You are more than welcome to see if it's true or not...
Arowanas on the other hand, can live with other fish, 2 arowanas may kill each other, 3 might work(you'll probably need a super duper big tank for this). We are just warning you on what's to come and how to avoid any casualties.
I'm just sharing what I've read around here, I have zero experience with these fish but I think I have some basic knowledge.
I need some experts to back me up, lol.