Sorcha - just re-read this and noticed how you suggested to start the siphon. I'd always been under the impression that you should never put the end of the sterile tube in your mouth - it ruins the sterility.

What I do is pinch the middle of the tube while it is in the hot water so that when I lift it out it doesn't lose any of the water inside. I put one end in the jug of must and the lower end in a jar or glass. Unpinch the tube, wait for the must to reach the jar, then repinch. Move the tube to the new jug, unpinch, & let flow. Easy way to start it and I don't compromise the sterility of the siphon tube.