Liquid IV is really good, but some people dislike the taste. I enjoy it, but Fox complains that it tastes like salty lemons. It does, but I like salted lemons, so I'm happy. The tangerine flavor is pretty good, too, I picked up some of that on sale. It's a bit pricey, but it seems to work, and if you're just drinking one a day it's not that bad. For long runs I sometimes pour two sticks into a 1.5 liter pouch.

Fox is a fan of regular old Gatorade. I find that the lemon-lime flavor is like a time machine directly back to high school band camp, LOL.