Houston we have a problem

So I'm still trying to figure out exactly how I'd like this to run. I was able to setup the pump onto my reactor however I keep getting air pockets throughout my tube assembly and am trying to figure out the best way to fix this. Whether it mean I change my pump assembly around or figure out another plan of action. Water is currently being pumped from the bucket below into the right side of the assembly and then gravity fed back into the bucket from the left side. Below is a current picture of my setup.