Embodiments are described for reducing pathogens in a fluid. The embodiments may include systems, apparatuses, and methods. Embodiments may provide for a flow cell with a plurality of channels through which a fluid to be pathogen reduced is flowed. The flow cell, and fluid, may be illuminated from more than one direction to pathogen reduce the fluid. In embodiments, the fluid may include a photosensitizer to aid in the pathogen reduction process.