Thank you for the reply. I'll definitely do all of the smoothing that I can before I install a liner. A couple of follow-up questions concerning the liner option:

1) What would be the best way to secure it at the top? Should I bury the top part, place heavy rocks on it, or secure with staples?

2) How should I secure the bottom section of the liner? If I don't weigh it down some way at the bottom won't it have a tendency to float up?

3) I believe that some liners are toxic to fish. Is there any type of liner I should avoid? How thick of a liner should I get?

Thanks again for the help!