Skimmer problems

I turn to you all for help again. I got I new skimmer so I pulled off the old skimmer and put it on another tank. Needless to say it don't seem to work on this tank. I cannot seem to get it to produce micro bubbles. I can take it off that tank and put it back on the old tank make no adjustments and it work like a champ. I am baffled I have attached a picture of what it does on the tank that don't produce micro bubbles.

 

Airflow is what I thought the problem was. I blew threw all the lines and cleaned everything up. Still no luck but I can hang it right back on the old tank and away it goes.

 

Problem solved! The salinity is not quite up there yet. It's a fresh setup.