Our "new to us" 26S sat for a summer with water on the cabin floor. It left tea colored stains about 3 inches up the sides. I have tried oxalic acid, CLR and several bathroom "miracle cleaners" and nothing works. Any suggestions would be appreciated. It's not life threatening, but it's ugly... Why the water? A previous owner decided to install a speaker in the front of the cockpit footwell. He sawed a huge, irregular hole about 10 inches in diameter and installed a plastic inspection port - with 2 screws and no caulking. He then cut another hole in the inspection port to mount the speaker. When the boat is on the trailer, ALL water runs into the cabin (bottom of hole is only 2 inches above cockpit floor) and none down the drain - DUH!! Chris