You run your bath, add the cleaner, watch the gunk emerge, drain your bath, and then clean off the gunk!Promising review: "It's disgusting to see what comes out of your jets when you use this product. I can't believe we bathed in this! I've run bleach and dish detergent through my jets before, and that combination never cleaned with this efficiency. I highly recommended this product." —Amazon CustomerGet it from Amazon for $16.99.