A centrifugal pump impeller comprising: an axis of rotation; an inducer end opposite from an outlet end along the axis of rotation; at least two main blades; at least two secondary blades; wherein the inducer end comprises an inlet eye; wherein each main blade is a continuous ridge extending from a main blade leading edge to a main blade trailing edge; wherein each main blade leading edge is adjacent to the inlet eye and each main blade trailing edge defines a first radius of the outlet end; wherein each main blade comprises a transition region between the inducer end and the outlet end, such that each main blade comprises an inducer end section, a transition section, and an outlet end section; wherein in the inducer end section, each main blade follows a helical or spiral path around the axis of rotation from the main blade leading edge in towards the transition section, and wherein each main blade defines a continuous inducer channel between itself and an adjacent main blade; wherein the outlet end section extends radially, perpendicular to the axis of rotation with a blade height that is parallel to the axis of rotation, extends from the main blade trailing edge, and ends the transition section; wherein each secondary blade is a continuous ridge extending from a secondary blade leading edge to a secondary blade trailing edge; wherein each secondary blade leading edge is disposed between two adjacent transition regions of each of two adjacent main blades; wherein each secondary blade trailing edge defines a second radius of the outlet end which is equal to the first radius of the outlet end; wherein each secondary blade defines two outlet channels (128, 130), wherein each outlet channel is defined by a first wall, a second wall and a floor that connects the first wall with the second wall, wherein the first wall of each outlet channel is one surface of a secondary blade and the second wall of each outlet channel is a surface of an adjacent main blade that faces the surface of the secondary blade defining the first wall, wherein the floor of each outlet channel is the surface of the impeller connecting the first wall to the second wall. an axis of rotation; an inducer end opposite from an outlet end along the axis of rotation; at least two main blades; at least two secondary blades; wherein the inducer end comprises an inlet eye; wherein each main blade is a continuous ridge extending from a main blade leading edge to a main blade trailing edge; wherein each main blade leading edge is adjacent to the inlet eye and each main blade trailing edge defines a first radius of the outlet end; wherein each main blade comprises a transition region between the inducer end and the outlet end, such that each main blade comprises an inducer end section, a transition section, and an outlet end section; wherein in the inducer end section, each main blade follows a helical or spiral path around the axis of rotation from the main blade leading edge in towards the transition section, and wherein each main blade defines a continuous inducer channel between itself and an adjacent main blade; wherein the outlet end section extends radially, perpendicular to the axis of rotation with a blade height that is parallel to the axis of rotation, extends from the main blade trailing edge, and ends the transition section; wherein each secondary blade is a continuous ridge extending from a secondary blade leading edge to a secondary blade trailing edge; wherein each secondary blade leading edge is disposed between two adjacent transition regions of each of two adjacent main blades; wherein each secondary blade trailing edge defines a second radius of the outlet end which is equal to the first radius of the outlet end; wherein each secondary blade defines two outlet channels (128, 130), wherein each outlet channel is defined by a first wall, a second wall and a floor that connects the first wall with the second wall, wherein the first wall of each outlet channel is one surface of a secondary blade and the second wall of each outlet channel is a surface of an adjacent main blade that faces the surface of the secondary blade defining the first wall, wherein the floor of each outlet channel is the surface of the impeller connecting the first wall to the second wall.