if they are leaking then its the inner plug and over wicking, adjusting the plug has stopped this, i had one that over wicked , adjusted the inner plug and stopped it, then put plug back to original position and it over wicked, adjusted the plug and stopped it. i wont be aorund till late tonight so ill make another video, its rather simple. i was not getting any juice leaking on that one form the black silicone, it was simply over wicking and easy to fix., it cant leak form the bottom of the cart, it can only leak by going up and in and then down the main tube, thats a over wicking issue, which means they do wick well, but you need to adjust the inner plug properly if that happens.