You want to get a nice little vortex going. The point is to work in some oxygen, and keep the yeast suspended, not create your own mini natural disaster.
I like to turn it up as high as I can get it without throwing the bar for the first 10-20 minutes, to get some oxygen worked in there, and then turn it down a little so I have a nice gentle vortex to keep the yeast suspended.
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On Deck: Belgian IPA
Secondary: Traditional Mead
Kegged: APA, Cream Ale, Belgian Ale, Sour Belgian, Barrel Aged RIS