Abstract: A dishwasher having a removable filtration system includes a main coarse filter screen having a central opening for removably fitting the filter screen around a water distribution manifold. The filter screen includes an outer circumferential rim portion have an elastomeric seal over-molded thereto which is press-fit into a channel in a lower sump unit such that the filter screen is suspended over a sump enclosure. A finer, secondary strainer extends through the filter screen and provides secondary filtering of washing fluid entering the sump enclosure through the filter screen. Preferably, the filtration system also includes a non-removable or backup strainer which provides coarse straining of washing fluid should a user fail to properly reinstall the removable filter screen and/or the secondary strainer.