It is not uncommon to have air in the line between the needle and the carb however; too much air can be a problem. Thinks for you to check.
1) Be sure your pressure line (the brass tube) inside the tank goes to the top of the tank. The line should be out of the fuel so it does not blow bubbles in the fuel.
2) Be sure your pressure hose is attached to the pressure line on the fuel tank not the vent/fill line (if you use a 3 line system.
3) Be sure the line between the needle and carb is not split.
4) Be sure the o-ring on the needle is in place
5) Be sure the nipple fittings between the fuel tank and the needle are tight and the gasket is in place.
6) You can use extra fuel line on the pressure hose (about 6 to 10 inches) coil it up and use twist ties to keep it neat. The extra line creates a buffer between the fuel tank and the muffler to smooth out the air going into the tank. It makes the air more constant and gets rid of the puff puff puff effect that can sometimes cause problems.
7) If you are getting air bubbles in the hose between the tank and the needle you may have a split in the brass tube in the tank. With a full tank of fuel hold the plane nose down so the fuel covers the brass tubes. If the air goes away I would look there.