I have only read your question and none of the answers but If your tank REALLY wasn't leaking you wouldn't find any juice on your connection. Therefore, the problem has to be the tank. I have a phiniac tank and also use boge cartomizers. I also have some leaked juice on my connector but it's such a tiny amount of juice that I don't have to bother cleaning it for WEEKS. It has to be the tank! No flooded carto will lead to that problem!
Perhaps not in your experience. There are many things that can cause juice to appear where it's not supposed to be. From badly flooded carts, weakened or damaged o-ring gaskets, poor sealing of the tube's end caps, and even the technique one uses when vaping on a cartotank.
It would seem to appear from the OP's last comments that his problem WAS a bad carto.