Healing stream totem stacks and is enough to heal through pretty much all instances.

Healing Stream Totem, Totem of Wrath(talent) are the only useful stackable totems I believe. I've not tested all though and only level 39 myself on my shamans.

Oh, and Tremor totem stacks if placed in intervals.

For example: (I'm not sure I formatted the reset timer in these macro's proper, this is of the top of my head just to show you what you should consider making totem macro's. )

Shaman 1: /castsequence reset=12 Tremor Totem, Healing Stream Totem, fire totem, air totem

Shaman 2: /castsequence reset=12 Healing Stream Totem, Tremor Totem, fire totem, air totem

Shaman 3: /castsequence reset=12 Healing Stream Totem, fire totem,Tremor Totem , air totem