Gorfz, I have the same problem and I don't think mine is due to too little flow. I originally had 1 u tube and added a second, while increasing the size of my return pump. This greatly reduced the priming problem. I don't have to prime mine every week but it's often enough. I've just purchased a CPR overflow and will be installing it today. I just need to get an aqualifter pump to add to it now. As far as I know, an aqualifter can be used in the same manner with U tubes. I'm not sure of the exact procedure but I believe it involves drilling a hole, siliconing tubing and hooking the tubing to the aqualifter pump. Each U tube should handle 600 gph. I've ran mine for 2 years with only 1 major problem. That was recently when a snail made it's way all the way through and down into the drain hose where it plugged!! I was woke up recently by Angie to "The 75 is flooding!!!" Dang Turbo snail. Hence my decision to change over to the CPR Overflow.