red sores

My daughter recently got me an adult Emperor. All has been going well until today. I noticed two sores on him, one one each side. I attached a picture. All the other fish seems fine. Just for reference it is 125 gal other fish include foxface, hippo tang, clownfish, tomani tang, bangai cardinal...

Hi everyone & Merry Christmas! My yellow tang recently became extremely ill and I almost lost him. He got into a fight with another tang, got a few scratches on his side and it progressed into a nasty looking red rash. I began treatment with antibiotics because all the information I could find...