Your going to have to replace the tank. It will quickly get to the point where you will break down due an overheating motor.....if you take it to a shop your looking at about 600.00 parts and labor. If you look on ebay, you can get a new Behr or Nissans radiator for about 140.00 and do the job yourself, which while time consuming, isn't a bad job. I did the repair in my driveway about 8 years and used a Nissans. I wish I used a Behr because the drain plug set up is much better. But the Nissans is still leak free. Don't take the car on long trips till u get it fixed.