Unless you have 500 gallons and really over a thousand,dont buy an Arowana. Mine in a 240 was around the 32" mark. She jumped out and I never bought another large fish again. It was a pet and for years I could only wish she had a huge tank. It sunk in to me..scale. 3' fish in a tank 2' wide,8' long is not right.
Now 30 years later I have Rainbows and Molly's in that very same 240 and they think its a pond. Scale. Proportions. Think of the fish.