I seem to remember learning that the colors change at certain depths. I thought red turned to blue or somehting like that after a few feet. But I really thought that red and white stayed visible for the deepest before they go away hence all the white and red salt water lures...I still think its a gimmic except for in Oregon. The smallies hit the red hook on a crank bait. If it was in the front or in the back then that was the hook they were pinned on.