Got a new K5 recently and all three got new wicks Wednesday evening. Nearly identical coils/wicks in each. All were bone dry through Thursday. Yesterday the new one (which was the most heavily used) had just an insignificant little bit of juice at one of the vents. By today, again the new one had just a little blot of juice and the other two were doing their usual seeping, including the one that had very little use. This seems to suggest is that it's not usage related. The most heavily used K5 had very little seepage after 2.5 days of use, whereas the one that was used very little was seeping big time after just sitting there most of the time. I'm gonna replace the top cap ring on the heavy seeper and see if that makes a difference. There's plenty of wick in the wells and the coils are at least 1.5mm above the air hole.