Filter structure with enhanced dirt holding capacity

A fluid filtration device containing a composite filter media having a coarse porous polymeric nonwoven interlayer located between first and second polymeric fiber containing filter mats. The fiber diameters of the fibers in the first and second filter mats are different from each other, and each filter mat has a different pore size rating. The first and second polymeric fibers in the filter mats can be electrospun nanofibers. The interlayer has a coarser pore size when compared to the either the first or second filter mats, such that the resulting composite media has an increased dirt holding capacity compared to filter layers that are layered directly over each other without the presence of a coarse interlayer therebetween.