So it worked fine with no air in the U tube until today and it was just creeping water through again like in the horribly out of focus picture above. A lot of bubbles are coming from the intake end and I do suck the air out with a 1/4 airline, which i love so much to do. Are you saying to raise the box or lower it? The next time it loses water I will check it again thoroughly for hairline cracks. If there is a crack is there a repair that can be done or just replace it? I have wondered if flow might be the problem the bubbles going through it move pretty quick but i don't remember how fast they moved before I got the new pump and it is always the same tube getting the bubble. I worry about changing my pump speed due to possible overflow.