Spencer M, Each Vertex CoActive Airststion with two discs on each has an operating cfm range from 1 cfm to 2.5 cfm per station.In the neck area since it has some depth just install the Standard 2 disc station. Your pond would have a total of 4 discs in two areas.If your pond was more bowl shaped and deeper we could get by with 1 Airstation.PS If you drain it for a motorcycle track we can use a smaller unit yet
