new to building ponds

[wayne sandland]

please can anyone tell me the difference between a vortex and a venturi and what is the best for koi ponds

 

[HARO]

A vortex is a device that swirls water around to settle wastes at the whirlpool's center. A ventury is a restriction in a water line that causes air to be sucked into the water stream for the purpose of aerating a pond (or filter). John