Proper Amount Of Surface Agitation?

[afmo]

Title says it all, i know surface agitation is essential for gas exchange etc, but how much agitation is the right amount. are ripples enough or should you have a frothing type action? I was just looking at my tank and found myself curious.

 

[ox5477]

Theres no real right type of agitation I would think, just as long as it is not still. The surface of my water in 10 is a good roaring flow only becuase in using a maxi900 in the small tank and it creates quite a tornado. But in my 55G fresh, the surface only barely moves around but thats enough.

Water movement means transfer of gasses so like i said, no real exact good amount of agitation, whatever you like or whatever fits into the tanks design.