He's a beauty, LBF. I really do think that the killies don't get enough attention. Some of them rival marine fish in their colors.
Sakura, I did have my big guys in a 29 gal for about a year before I came to grips with the fact that I needed to upgrade them. I had one with a band of black across his eyes; he was so cute. With regular water changes, it's not the end of the world, but they will be bouncing off the sides. I know mine did.