Abstract: A passive anti-clogging device for feeding water into marine jet pumps, which displaces the laminar flow around the trailing surfaces of the intake port, such that foreign debris and grass are precluded from clogging the intake to the jet pump. The primary component of the invention comprises an exclusion plate that is placed in, or immediately below the intake port, and affixed to the breadth of, or becoming a part of, the trailing edge of the intake port, leaving an opening, or slot, between the exclusion plate and ride plate, or bottom of the vessel, which, when at rest, allows the passage of water only from its anterior and lateral extents, thereby excluding the flow of water into the device from directly below or behind the plate. The edge of the exclusion plate angles or curves from a forward central point or apex to a back point at the trailing edge of the intake port, providing a fair surface to resist laminar attachment of debris, marine vegetation or other debris.