Kurt's answer is right-on (no surprise).
And there is also an alternative solution:
Throw out the filler and just drip directly on the atty. Way back a long time ago when I used carts, I was topping off and fiddling with the cart (with less effective results) as often as I now drip.
And, when dripping is inconvenient (e.g., while driving), you can use cartomizers: 510 cartos for the Joye 510 and eGO/Tornado and Kr8 cartos for the Kr8 or any other model with an adapter.