Product: Filters - UV Ultraviolet
UV filtration destroys single cell algae which is the main cause of green water. Can be combined with bio filtration systems to maintain a crystal clear pond. UV Filters will work excellent if you have a pressurized filter to back them up. You will need a pump to run the water through a pressurized filter that will clear most of the solid matter and then allow the water to pass through the UV filter.
Nothing can detract from the look of your backyard pond worse than green-colored water. Problems with water color typically result from the presence of single-celled algae in pond water, and ordinary filtration systems typically aren't capable of eliminating these organisms.