That pond will be appox 8000 gals. (if my math is correct). Try to get 1 full turn over. The problem w/ such a small filter box is @ 8k GPH it just might blow the doors off that filter. Like Guppy said, use a large trough or build a smaller pond that is basically a wetland filter. Fill w/all kinds of plants to have crystal clear water. If you do use big trough or sm. pond filter, make sure it is located above the main pond. A smaller pond below the main pond can easily overflow in a power outtage or heavy rain.