Nice looking fish. Not a Julii, or even a Corydoras. From that picture it looks more like a Synodontis. Couldn't say which one, but I would guess possibly one of the many hybrid versions you find in pet stores.Can someone tell me if this is a Julii or if not what is it?
I don't know what a "tiger cory catfish" is, sounds like a generic pet store label or a random google search result, but the picture you posted is of a Sterbai Cory