I have a 270 gallon tank with a variety of different "monster" fish. In the tank I have 2 arowanas, a Florida gar, 1 stingray, a peacock bass, and some bichirs. I do 50% water changes weekly. I was gone for for a few hours and when I can back home I found my gar with a broken back. I know it was from the peacock bass because he killed many other fish I use to own. The gar is still able to move his caudle fin and eat but he is in bad shape. Should I ramp up my water changes? What can I do to help him?