We built a small 2500 gallon in-ground pool, and one of the walls is a waterfall. The pump we were going to use worked fine, but was much louder and was struggling so we decided to find something else. The wall is about 7 feet above the surface of the water (water flows to the very top). We are tempted to use a submersible fountain/pond pump since it will be dead quiet in the water and there are some that have a max head of 10-12 feet which would work for us. What other pumps would work for us? We basically need an inline pump (that is fairly quite while running) where the inlet goes into the pool and the outlet goes up a 3/8" or 1/2" tube to the top of the wall. Flow rate can be only 10-20 gallons/min at that head height.