For those who have purchased this and not had good results I can share with you the modifications I made that are producing good results. First the two wick holes need to be enlarged i used a small drill bit that just slightly increased the size of the wick holes. you will also need to drill a tiny hole in the top portion of the metal cap just where the crease is that goes around the cap the hole needs to be no bigger than the crease (seam) that encircles the cap 0.7mm to 0.9mm this will dramatically open up the air way and make for a effortless draw.After I made these two modifications I have been very pleased with the Viva rebuildable Tank. If I can help anyone out feel free to e-mail me D. Johnson