Cetaphil Before or After I use a Product with Benzoyl Peroxide?

Should I use Cetaphil Gentle Cleanser before or after I use this cleanser that gets rid of acne and prevents them, that contains 10% BP? Should I use it before, to clean my skin of the night before of using BP, or after, so that I will clean and moisturizer my skin? The only thing is that I think if I use cetaphil after, it will wash away the BP. What should I do?Cetaphil Before or After I use a Product with Benzoyl Peroxide?
You only need to use one cleanser, so if you have acne, use that one.