[Joe]

I had a similar experience a few years ago. I exited a service station that had a deep dip at the curb and scraped the bottom of the tank. By the time I got to a campground all the water had leaked out. I think it was at a WalMart that I found a 'stick' of epoxy that was supposed to work under water. It was about an inch in diameter and a couple of inches long. The directions said to massage it into a ball like you would do putty. That would mix the 2 ingredients and start the chemical action. I cleaned the tank where the hole was, began mixing the stuff per the directions and then pressed the 'glob' onto the tank. I tried to work it so that some of the 'glob' would go inside the tank. I held it in place for several minutes. I could feel the heat from the reaction but it wasn't uncomfortable. When I thought I had held it long enough, I left it to cure. I waited a few hours to use the tank and never had a problem. A year or so later when we traded the trailer it was still holding.

Good luck

Joe