Susan Biddle Ross is a character on Seinfeld, played by Heidi Swedberg. Susan, an executive at NBC, first appeared in the season 4 episode  The Pitch , in which Jerry Seinfeld and George Costanza pitched the idea for their sitcom to Susan and her fellow executives.
The best solution is to remove the tank and drain it. You can also try and siphon out as much as you can and put STP Gas treatment or any other alcohol based de icer in. It will take several cans of this plus fresh gasoline. If water has reached your fuel filter this will have to be replaced also.
Plain white vinegar (which is the cheapest type of vinegar) will work incredibly well to dissolve, clean-out and remove rust from inside a gas tank. First you have to take out the gas tank and remove all the old gas. Then pour in straight white vinegar and let it sit for several days. It will depend greatly on how rusted out the gas tank is for the treatment time and the number of times the process has to be repeated.