Oh I see what the confusion is. My skimmer is the TF1000 in-sump, it uses a seperate pump to feed water, and the Oceanrunner 2700 is just for air and recerc.
In mine if I did not restrict the air input the skimmer would overflow with no water running through it, if I ran as much water through it as I would like to (about 200GPH MFG reccomendation) I had to cut the air back by almost half.
With the old Rio that used to run this skimmer I did not have this problem, but with the new pump it really bugged me that I could not use my full capeability.
Whiskey