Ever wonder what different size gph pumps would look like in your pond? Rocks 'n' Roots (586-752-4900) has given you a visual of your options. We've displayed 1,000gph, 2,000gph, 3,000gph, 4,000gph and 5,000gph pumps to make your selection easier. Each of these waterfall openings are 14 inches wide. The pumps are placed 4 feet below their respective waterfall box.