yep...
as i suspected, it's prolly got nuthin to chew on...
hence forcing you to crank up the water level until it just fills the cup,
there's no adjustment zone at the moment..
i suspect tht will change drastically with the addition of
the live rock and then bioload. as for what is the best place to set the internal level of the skimmer,
that will remain to be determined by your stocking and feeding habits... you'll easily find the sweet spot once your tank is set up in it's permanant configuration. it also depends upon if your looking for wet or dry skimmate, I would suggest to you that wet skimmate and the rate of it's removal makes it a better level to acheive than dry skimming. once there's a bioload, I would start out with the bubble breaking point being in the bottom 1/2 of the collection cup, and the water level being in the top section(if not the very top) of the reaction chamber.