A pond pump will help circulate and oxygenate your pond water. A waterfall pump is different. For a waterfall, you’ll be pumping water to create the water feature, and you’ll need to determine how wide you want your flow of waterfall to be. Every inch of stream width will need to pump 100-gallons-per-hour at the height you’re pumping. For example, if your pond pump needs to lift the water up 5 feet to the top of the waterfall, you’ll need a waterfall pump that moves 100-gallons-per-hour at 5 feet.