Hi, Yesterday I was grooming a little patterdale terrier and any time i went near its left ear it tried to bite. So in the end i muzzled her and got my tutor to have a look. She sed that the dog had an ear infection and to tell the owner. When i told the owner she asked how to treat it but i didn't know so just said to go to the vets. Is this right or is there a powder or something to get from pet shops?