Abstract: A screen apparatus for improved separation of particulates from a fluid stream. The screen is configured and arranged to filter relatively large particulates from the fluid stream as the fluid stream passes from a storage chamber of the tank to a tank outlet. The screen is removably affixed to a diverter, such as a baffle, used to divert a portion or all of the fluid into the storage chamber. The screen is preferably shaped to substantially conform to the shape of the diverter to aid in the smoothing of the fluid flow within the retention section of the tank. The screen may be entirely porous, or it may be non-porous at its leading edge to minimize particulate build-up at the transition from the tank interior wall to the screen. The apparatus may optionally include a second screen to provide additional filtering of floating particulates as the fluid level in the tank exceeds the crown elevation of the inlet.