OK fellas-- now for a real dummy enquiry. I spent 6 years in the US Coast Guard, time in Boston Whalers and then owned a 17 foot sail boat. Plenty of time piloting small craft. So now I move out here to the Missouri River country and finally find a 1994 17-foot deep V hull bass tracker in excellent shape at a fair price. I got 2 transom plugs with it-- a snap over rubber plug and a twist in rubber plug with a brass T-handle. Problem is: this boat's got 3 holes down there. ALL below the water line. The guy I bought it from couldn't explain it-- he'd bought it as a toy, used it once and stored it for the rest of the season. Now, I am completely new with live wells and aerator systems. Could this 3rd hole be an inlet for the live well and if so it would have some sort of back-check valve to prevent flooding. This hole is higher than the other two on the transom and has a white plastic collar or lip on it. If it is for the aerator/live well system, does it serve a double function as the outlet for the bilge pump? I checked out the motors for the bilge and the aerator pumps before I bought the thing and heard them whirring so they seem to be in order. So whats up with 2 hull plugs and 3 holes? I ain't even taking this near a mud puddle until I am straightened out. Thanks in advance.