My tomcat was in a fight and got his ear badly scratched. It started smelling really bad as the puss formed, and the whole scratch was filled with yellow puss. He was in a lot of pain. So to clean the ear i put very warm water in a small bowl and added quite a bit of apple cider vinegar. Then i dunked tissue paper into the water & apple cider mix and squeezed it out into his ear (i had to get another dry tissue to hold into his ear-drum so the water wouldn't run further into his ear and upset him). It cleaned it out very quickly, after a few hours the crust had gone and the puss was dispelling. I repeated this in the morning, and he actually seemed to enjoy the warmth of the water on his painful ear, so he never even flinched when i came close with the apple-cider water. it's worked for him ! It's easy on the skin, not harsh like other medication / antibiotics would be.