I use silcone aquarium tubing. It holds up very well, is super flexible and no taste to speak of. Of course, if you have to use it to sip water out of a small pool or a seep, it will likely taste nasty anyway.
The main thing that I like about the silicone tubing over other type plastics, is that it is really durable and flexible. Mine is aqua blue color and about 1/8" ID.

http://www.drsfostersmith.com/Product/Pr...p;N=2004+113793