My Mastiff had dark brown, almost black diarrhea on my new cream color carpet! I scooped up as much as I could and was left with a large dark stain! I thought the carpet was ruined! I had just received my shipment of MPP and decided to give it a try. After all, what did I have to lose? I sprayed the stain and waited several hours. When I can back the stain was visibly lighter! I sprayed it again before going to bed. In the morning, it was lighter yet! I sprayed it again, and after work, I noticed the stain was now a light tan. I will continue to spray it at 6hr intervals until it is gone. I am so pleased with the results! I thought my carpet was ruined! I highly recommend this product!