I am not looking for a specific flashlight, but I would like to know what type of light I need to see fish in shallow water while standing in a boat. The light will be about 4 feet above the water and I would like to see out 15-25 feet. Should I try incandescent or LED? Should I use a filter or colored lens? I tried a P.O.B. spotlight, but it does not seem to penetrate the water.