help with u-tube bubbles

Ok, I know that my overflow box is rated for a lot more than my return pump and I'm having remove the air about every 8 hours or so. I'm trying to find an uplift pump, but I'm not having any luck finding one locally. I'm read that I could use a smaller u-tube and that should fix the problem, but apparently those are specific to makers and aren't readily available either. So....I'm planning on getting a piece of hose that will fit the ID of the u-tube to size it down some. My question is: Can I just stick a 2" piece in the inlet side of the u-tube to slow the flow, or do I need to line the entire u-tube.

Thanks for any help.
 
I found an uplift pump and it's working perfectly. I'm not even going to mess with making the u-tube smaller.
 
Top