Have 4 holes in my overflow, two one inch and two 1.5 inch. Set up one 1" as the return and planning on using the other 3 for bean animal. Set the length of the full siphon 1" at 6" below the weir, and a 1.5" emergency at 1/2" below the weir. Now the question is how tall do I make the "durso" style bean secondary 1.5"? I can't seem to find anything so far.