[Aceroassert]

I recently rescued a pit bull who is about 18months old, 65 lbs. He is great around me, listens to my commands. I also have a smaller dog, Bruno, who is a mix between a beagle and basset hound, about 25lbs. They do not get along, I think it's because Bruno gets jealous easily and doesn't like when bigger dogs jump at him wanting to play. I have them separated in the house and do not let them outside together because I don't know what they will do to each other.

A few nights ago I was outside with Koda for about 10 minutes and then put him on the leash so my sister could let my other dog out. She threw the ball for him and Koda was fine as I walked around the yard teaching him to heel on the leash while there were distractions around us. Last night I was in my back yard playing with Koda and then my other dog was inside barking because he wanted to come out. After a little while I put Koda's leash on him and gave him to my sister who was outside talking to a neighbor. I let my other dog out to throw the ball to him and he ran over to where Koda and my sister were. Koda started acting like he wanted to play but my other dog didn't want to and they started fighting. Koda bit down on Bruno's ear and would not let go. My sister and I were trying to get Koda to let go, first by pulling back on his leash and hitting him (not a beating) and he would not let go. I also tried to put my hand on top of his mouth and squeeze his gums, I've heard that is a way to make the dog drop a toy (I'm not sure if I explained that method right, sorry). Eventually he let go and I brought Koda inside and put him in his cage. He knew he was bad. Bruno's ear was bleeding but he will be fine. We cleaned it up and he wanted to play with us again.

I don't know what to do, should we get rid of Koda, introduce them to each other again in a few days when they both are on leashes so we have control of them? I'm worried that if we let them be together again, they will fight again and Koda will hurt Bruno really bad. PLEASE HELP ME.