I agree that the siphon system is great in many ways. I am eager to use this system for my pond that I will build next spring/summer. One question, though... How reliable is the siphon system in northern climates such as my home state of Ohio. I am concerned that the vent pipe could freeze up in the winter and the pond drain all the way down because the vent can't work. I thought about opening up the vent pipe at the tee and then relying on the emergency spillway to control the water elevation but then you run the risk of erosion. Does anybody have any experience or knowledge on this issue.
Thanks
