All of the suggestions are excellent and you should check them out. If none of them prove to be the problem it could be what I had a problem with years ago. My boat never took on any water until it started to. One evening when I pulled the plug several gallons of water came out. I started searching, checking hose fittings, livewells, everything. Nothing yet the water kept getting in. I even put a lot of water in the hull in the driveway and watched -- no leaks emoBang emoBang . Finally I noticed that the boat took on more water when I made runs when the lake was rough. I discovered that the silicon seal under my rub rail had deteriorated and when I was running in rough water the constant splashing up against the underside of the rub rail was getting into the hull. I just got a tube of marine silicon and a caulk gun and neatly resealed the underside of the rub rail. Problem solved. The boat never took on any water even in very rough conditions. It is worth a check, just look under your rub rail where it joins the hull. If you see gaps, especially in the bow and side areas where spray hits that might be your problem.