Step 4 · Create a High Loop with the Drain Hose

This is the step people usually slow down on. Go finger-tight first, then a quarter turn. No rush — replay the clip whenever it helps.

To prevent dirty water from the sink from flowing back into your dishwasher, you must create a 'high loop' with the drain hose. Take the corrugated drain hose from the dishwasher and pull it up as high as it will go under the sink, ideally touching the underside of the countertop. Secure the hose at this high point to the back or side wall of the cabinet using a pipe strap or a heavy-duty zip tie. This ensures that the water level in the sink would have to be extremely high to backflow into the hose.