Others have chimed in with some good info regarding this beautiful fish. Your current small tank is unsuitable and even when you get round to getting a bigger tank you need to be buying multiple balas really, they're better, and more impressive in groups. I bought four in 2015. One died the day after I got them, the other three are between 9-11" now.
They're not the fastest growers ime, even though they can be gluttonous, but they are one of the fastest at swimming when they want to, they have a real turn of speed, even more reason for a big aquarium. They can jump too, as mentioned, so a good lid is essential. Never known mine to be aggressive neither.
I don't know about anybody else but mine make a right racket at feeding times. They have a slight underslung telescopic mouth and when they are sucking pellets up from the bottom of the tank their mouths dart out very quickly and they make what can only be described as a loud click.
All in all a great addition to a tank, if it's big enough that is.