Sharks do have both rods and cones in their eyes, which would indicate that they see in color. But remember that in very low light color is not discernible. When it is very dark at night we can't tell the difference between colors only the difference between shades of dark and light. Sharks are similar in that at the surface they can probably see in color, but at depth they only see in monochromatic shades depending on where they are at depth. Different colors have different wavelengths and can penetrate water to different depths.