[luke33]

40 for the neck is to much anyhow. I had to keep the foam level below the neck for it to work. I'm now holding steady at 32ish with my new recirc mod done with a different pump There are more complicated venturi's you can make that will pull 40scfh such as a 1" female pvc fitting that goes from 1" to 3/4" to 1/2" right before the air injector, that will work well as well, or jtcrews has a picture of another that works as well. I was just trying to post the easiest way to do it that no one would have a problem with. 30ish scfh is ideal for the neck on this skimmer. If it were 5" or so it could handle much more.