Blacking out Overflow U tube?

The lights are suspended high enough to light up the tube but that doesn't wory me, like I said, starting it is so simple that if I need to clean it once in a while, I have no isse's with that.
Reeron, I'm glad to have read your post. The water is moving so fast, I don't see an air bubble being an issue at all. Your post makes me feel a lot better. The water moves so fast, that when I had my initial bubble from starting it and not being able to get all the air out, it was gone within a minute after turning on the return pump.

 

I wouldn't worry about the algae. I have some serious algae issues in my tank yet the utube doesn't get out of control at all. As for the air...just make sure you have a lot of flow and you will never see air build up.

Note: Buy a quality OF box, you never know.