Pond Filter UltraKlean™ 3500 $250. new -$575.98 Bio balls, UV light treatment, backwash UltraKlean Pressurized Biological Pond Filter The Aquascape UltraKlean Pond Filter with high-output ultraviolet clarifier and integrated electronic bulb-saver filters ponds, providing pond owners with optimum water conditions and crystal-clear water. The unique sponge-free design minimizes maintenance and maximizes efficient mechanical and biological filtration. Bio balls, UV light treatment, backwash, 3 years old, used in a cleaned regularly pond.