Assume that the route must begin from the outlet located on the side of the tank - not from the outlet on the bottom of the tank.
Since this outlet axis is horizontal, the first segment of a self-draining route created directly from this outlet would not be sloped. This positioning would contradict the logic of a self-draining run and the route would be listed as Sick in the browser. First you add a fitting that provides a transition from the horizontal outlet axis to the route slope. For example, if the route slope angle is three degrees, first place a custom fitting with a bend of 177 degrees, like the following image.
