I wrote a self help artical to help you modify your ponds, or help you in the construction of a new one. If you have any questions about raccoon prevention please feel free to post in this thread and I will do my best to answer them. Click on the link, and check it out for me, and I am open to constructive coments.
http://raccoonremovals.com/about-raccoons/raccoons-eating-my-koi/
http://raccoonremovals.com/about-raccoons/raccoons-eating-my-koi/