noake -- first, welcome to Pond Boss. Glad you found us.
As for filling a pond with well water -- it is as our good friend Bill Cody always says -- "it depends."
It depends on your soil and water table. If you are in a sandy area with a high water table, filling with a well won't do much good. If you are in an area of heavy clay, with a deep water table, your chances are much better.
A synthetic or heavy clay liner can also be the difference between success and failure.
Tell us a little more about where you are located, a little bit about your soil types, a little bit about your water table, and a little bit about your watershed. With that, you may get more help than you ever could have wanted.
Regards,
Ken
