If you are looking for clear water, I think the only way you will achieve that is to either have a filter system, or underwater plants in the pond. Without something in the pond to utilize the nutrients in the pond (in the form of leaves, pollen, etc., etc.) you will end up with at the best a phytoplankton bloom, and at the worst FA.
I would talk to Bill Cody about steps that you can take to minimize phytoplankton and forms of algae in your pond.