Just water for me. I get enough electrolytes from my food. I have zero interest in anything sweet tasting. I'd consider mineral tabs for my water if they made such a thing. Military 1qt canteen on my saddle. If I were doing this professionally, I'd send an empty down in exchange for a full one, which is what I do at my real job, except I get it myself. Wet down the pile in the cover, and it keeps the water cooler through evaporative cooling. YMMV for cooling capacity. Humid here, so less cooling, but it doesn't get too warm before I've finished the bottle.