1. cut a hole in the top and put a rubber/plastic bladder type tank inside the old one to use.

2. if you just have pin holes in it use a sealing epoxy to paint the interior to seal the leaks. here is a link to how to do this. this post talks about doing it to a fuel tank but Jason of Bohdran has also done it to one or both his water tanks also I think.  http://downeasteryachts.com/in.....eplacement

here is a link to just some general conversation about water tanks on the DE's http://downeasteryachts.com/fo.....water-tank

Phil stephenson pulled and replaced his fuel tanks on his boat when he owned it..

http://philstephenson.com/file.....ey2008.pdf he talks about it here. you might contact him through his website and see if he remembers any details.

Scott

thanks
Travis s/v Seabird