Skimmer not working properly

[shine~on]

My protein skimmer isn't making enough bubbles to come to the overflow container. It's an AquaC Urchin. I replaced the pump which is a maxijet 1200 a couple hours ago, but it doesn't seem to be fixing the problem. What else can I do? Is there any other mechanical parts that could go bad? Does the interal part of it need cleaning?
I've also lowered the overflow cup to see if that had anything to do with it, but the bubbles just aren't coming up the plastic oval part.

 

[seasalt101]

have you adjusted the air venturi any?

 

[sagxman]

How old is it. Maybe the air valve needs to be replaced. Also, they don't always make much skimmate if you've just done a water change.

 

[matt819]

It probably isn't going to immediately produce skimmate, there is usually a break in period for skimmers....just let it go for a day then see what's in the cup.

 

[shine~on]

I don't know how to adjust the air venturi, where is that? It's a couple years old, where is the air valve? I haven't done a recent water change.

 

[shine~on]

I just cleaned the injector valve, we'll see how it goes!