We claim the ornamental design for a water filtration device, as shown and described.
FIG. 1 is a top, front, side perspective view of a water filtration device showing our new design;
FIG. 2 is a front elevation view thereof, it being understood that the right, left and rear views are duplicates of and are therefore not separately illustrated;
FIG. 3 is a top plan view thereof;
FIG. 4 is a bottom plan view thereof;
FIG. 5 is a top, front, side perspective view of the device depicted in FIG. 1 in an alternate operational mode; and,
FIG. 6 is a front elevation view of the device depicted in FIG. 1 in an alternate operational mode, it being understood that the rear view is a duplicate of and is therefore not separately illustrated.