I assembled a mercury vapor 175 watt underwater light to place in my boat slip. I was going to place it in the center at the front of the slip.

However another slip owner advised me to place it at the back of the slip. He stated my pontoon would cover most of the light area when I was fishing from the pontoon. If I placed it at the rear of the slip then the light would be at the rear of the pontoon where we fish when we fish the slip.

The slip is 13' wide, 36' long. My pontoon is 20' long. When I am not there I have the pontoon moored about 6' from the front of the slip, with about 3' on each side of the slip. When we fish the slip I pull the pontoon to the front of the slip and to one side so we have about 16' to fish at the rear of the slip and about 6' to fish at the side of the slip.

Should I place this 175 watt light at the front of the slip or should I place it toward the rear of the slip? The light will be placed about 2' from the bottom and generates a 20' circle of light when on.

I have read that crappie hang outside the light and ambush minnows that swim outside the light. If this is true then placing it at the front of the slip will place the end of the slip at the end of the circle of light. Then our hooks will be in the area where crappie are hanging out to ambush minnows.

If this is not true then the pontoon will cover a large percentage of the area that the light circle covers.

So where would the members of this forum advise I place this light for the best location to catch crappie?