Siphon feed question



I just got a [FONT=Verdana, Arial, Helvetica, sans-serif]Master S66 Studio Airbrush Set. This is my first airbrush, I know its not the best but its was a place to start. Anyway the question is, the cup that it has should it be sealed or be vented? The ones the set came with have a vent hole and leek at the stem.[/FONT]
they have a small hole for air getting inside because without it the paint can´t flow up to the airbrush!!!and by the way you should use the introductions section so we know you and greet you properly.:angel: