So far as I can tell, both my ProTanks are legit. The one that doesn't work I did try nekkid, not attached to the battery. It did have air flow going through. I also tried it on the battery, without the beauty ring ... nothing. So, like someone did suggest, it would appear to me that something, perhaps the airholes, are blocked when I put it on the battery. One of these days I will check it out. I think the next thing I try will be putting the base from the one that works onto the one that doesn't and see what happens. Process of elimination, right?
Now I finally see what everyone's talking about when I read how airy the ProTank is. I don't dislike it. I've been using a Vivi Nova for a few weeks now. What a difference when compared to the ProTank!