Hello,
For the first day or so mine still produced a few bubbles even when I had it at the full off position. After that it worked fine and still is some 2 months later. Make sure you have read the instructions correctly, it is possible that you may have missed a small step. I have a little problem moving the rubber tube from the first position fast enough to the 2nd position, by then the air bubbles start declining fast sometimes. If it doesn't seem to be working right after a day or two start the process over again. Hope it is working better by now.