An assembly (1) which is intended for use at an area (31, 32) for allowing a fluid to pass therethrough comprises a filter (10) for blocking items from passing through the area (31, 32) along with the fluid, and at least one anti-biofouling source (20) for emitting ultraviolet light during operation thereof for realizing anti-biofouling of at least a portion of the filter (10). The filter (10) comprises a filter body provided with apertures, wherein the actual filter body is at least partially transparent to the ultraviolet light, so that anti-biofouling of the entire filter (10) may be guaranteed, even in case the anti-biofouling source (20) is positioned at only one side (15, 16) of the filter (10) and/or is integrated in the filter (10).