Oh, glad you wrote. One cricket in the water should not cause this, do you recall when you had changed water prior to the illness or dead cricket? He may have stopped eating before you forgot about him for a week? Could it have been more than a week? A topical ointment does not work fast and how would it stay on if he gets wet? Is his skin any worse? You are going to start medication? what form, liquid? I have to ask alot of questions, otherwise I won't know. Did he swim because he ate or the water was changed? I can't figure out why he swam either. Maybe you can write and give more details? Thanks