It depends how clear the water is. I used the camera in the clear water at Perris in 30’ and could see forever. I tried the camera at Puddingstone when the clarity was 18 inches (at best) and 20’ deep was about the max. Even though the camera has a built in light that can be turned on from the monitor, if the water is dirty you just light up the sediment in the water. Kind of like driving in the fog and turning on the high beams, all you see is fog. In most applications 20’ is fine. Like I mentioned in an earlier post I have no remorse buying it. Heck $100 is cheep, one third the price of a GLX.

Henry