Replying to Line Freezing from Water Bladder/Reservoir

I have researched this on the internet and saw some pretty decent solutions. Just wondered if anyone had any more input on this. The tubing from my water bladder in my backpack freezes quite fast in moderately cold temperatures so I am unable to use it when skiing. My bladder is in my backpack and the tubing is threaded through my backpack shoulder strap sleeve. None of it is completely exposed to air. Albeit it is quite thin fabric.

Solutions I've found include:
-Buy an insulator sleeve for the tubing
-Put warm or room temperature water in the bladder when you fill it.
-Blow any water out of the tube back into the bladder after each drink
-Put Gatorade or some sort of electrolytes with the water to lower its freezing point.
-Put a little alcohol in the water

Anyone have any fool proof methods they use? Nothing is more annoying than going to take a drink and realizing your tubing is frozen solid.