I just got an Aqua C Remora and put it on my tank. This is my first skimmer ever so I would like to know how to set the height of the skim cup.

Which is better:

Higher up, the less foam, but it is dryer and darker.

Lower, more, but whiter and wetter.

Which is better? Is it better to get all I can out of the tank, or go for the darker stuff?