Power-head confusion

[Itainteasy]

I have a power head, not sure of the model. It works perfectly for creating current in my tank/aeration.

My question is. It has a small tube before the outlet, the tube has a small nipple attached to the end. WHAT is this tube?. I have it hooked up but underwater, because if I leave it out in the air it sprays a little water. What is this tube for?? I'm confused, it's my first time using a power head. Should I just eliminate this tube altogether? Leave it underwater? Let it grab air?

If u guys don't understand, which I'm sure u will I'll take a pic.

 

[bbortko]

It's a venturi tube for suckling air. I never used a powerhead so I don't know if they spray is normal but I would imagine you could use an airline tube suction cup and attach it to the bottom of your lid b so that any spray remains in the tank or just remove the hose completely if your not concerned with additional air.