The classic combination is arowana and stingray, your 330 tank will have no problem for them.
Edit:
I woundn't add the Oscar to your tank, its greedy eater will cause more harm than good but it's your choice if you're Oscar lover.
Edit:
I woundn't add the Oscar to your tank, its greedy eater will cause more harm than good but it's your choice if you're Oscar lover.






