Once in a while, I get some scratches in my negatives, and I am almost sure that they appear when I clean them with a brush (Adorama brush). Is there a fixer able to protect the surface of the film? I always work with Tetenal Superfix Plus for developing Tmax 400 B&W film, 1:9 concentrations, during 10 minutes. Is this a good choice? Thank you, Henry.