Mike,
Thanks great ideas. I will put the over flow into a bucket. That will cover the immediate issue. Yes this unit has venturi air inductor on the pump so air enters there. The pump is inside the tank while the unit is HOB. I have attached a diagram with labels. There seems to be no inlet control. But there are two outlet controls, I have marked. However, if I cut the flow back it builds back pressure into the skimmer and overflows the cup, as you suggested. Your suggestion of a control on the inlet would help a lot I think. It should dcrease the inlet flow.
All thanks for you help. It appears this is DIY unit since no one and all the searches I did cannot come up with the unit. It really has lots of air but a little too much if I cannot reduce the pressure in the unit. Everytime I cut back because it is on the outlet it just builds pressure and overflows the cup.
Sure would like to know what happen a week ago. Before that it was great. I will take the pump out and check it. Maybe something in there is causing too much air pressure?
Attachment 11542