So we took the boat out of storage for detail and other things to get it ready for the summer. After the swim platform had gotten wet I had walked on it then on to the sundeck. There were black marks from where my feet were. Is there something I can rub on the mat? My dad does not want to buy a whole new mat, but he does not want this to keep happening when people get in an out. I know that this has probably already been discussed; this just seems like the fastest way for advice. Thanks for all the help so far on all my other questions.