I just got my protank yesterday and tried it, I got plenty of vapor but it was too airy for me. So I did a search to see if anyone else has the same problem and I found plenty but not really a was to solve it other than using toothpick. I have an eVic and the eVic has air slots on the base so it makes it even more airy.
For those of you who doesn't like the airy vape on the protank. This is how I did it...


In the picture, you can see the air slots from the eVic and the base of the Protank causing the vape to be too airy.


I found a rubber thimble in my desk draw and cut off the bottom part large enough to cove the holes

Slide it on to the Protank and leaving only one hole exposed and to me, a perfect vape!!!
I know it's not great looking but I dont' mind since it's pretty easy to take the tank off and on and not having to stick anything in everytime. I hope this hlep some of you 
For those of you who doesn't like the airy vape on the protank. This is how I did it...


In the picture, you can see the air slots from the eVic and the base of the Protank causing the vape to be too airy.


I found a rubber thimble in my desk draw and cut off the bottom part large enough to cove the holes

Slide it on to the Protank and leaving only one hole exposed and to me, a perfect vape!!!