This part is not included and should not be used, if it is foaming over at the lowest setting, raise the skimmer. I use this same skimmer, I have it set so about 1/4-1/3rd of the intake is submerged and the pump speed is set to the 10 o clock position, it took time to get to where I could run it this high, I started with it all the way down and the more I removed in waste the more I could increase pump speed. The DC version is superior because you have a constant 2 part water to 1 part air, on the AC with air adjustment as you decrease air, you increase water and that ratio is less efficient.