I tried bleach with one of my other ones, the taste does make me feel a little sick. I've googled it a bit as well and they all say baking powder is the key, I just wanted to hear it from someone and not some random website.
What I need is the brushes, the mildew is just all over and I think I'll need to do some work on the tube as well.
Edit: I definitely need the brushes, the tablets just loosened up some of the mildew. When I tried flushing it out through the tube I kept seeing splotches of mildew coming out.