I'll add my voice in here saying you most likely don't need anything special on tour. We rode from Alaska to northern Peru drinking just plain water and were just fine. Looking back on it, I think there were a few times in Central America that I should have added something to my water - but we survived fine on water.

Going through the desert of northern Peru the water was simply not enough for me - hubby and kids seemed to do fine on the water though. For that stretch, I simply strapped a 2-liter bottle of Inca Cola on my bike and took a swig or two of that for every bottle of water I drank - seemed to do the trick. I'm not sure what was in there, but whatever it was it helped.

Now that we are out of the desert, I'm back to plain ol' water and it's just fine.