How to stop slurping?

[authentic]

Herbs drain, I have a gate valve to restrict flow ( a la red sea reefer) I dial it in and it still pulls a vortex from the surface.I cut the drain down to about 4-5 inches below the surface and it still breaks the air.saw that a new type overflow was built reading reefbuilders...anyone have a DIY?

 

[vertigo01]

Everything I have read regarding a Herbie overflow suggests a 1" full siphon, be 6" below surface.

 

[authentic]

Thx