Thank you very much for the information. Horsey, that is what my barn manager does for her horses which got me wondering if I needed to. Ryle, the article was very informative! I certainly understand how electrolytes work now, but I am not sure if my horse receives enough exercise or if our heat and humidity makes it a good idea to supplement with electrolytes. We certainly aren't going 25+ miles ANY day (or any week for that matter), but it has been in the 90s with higher humidity lately, and he is sweating mildly when standing in his paddock. We will sometimes do lighter work than normal, light training in the arena for 15 minutes, then trail ride in the shade for an hour. And I gather from the article that his salt block can also help. Do you think a minimal dose of electrolytes would be a good idea for our weather and work, or should I just leave well enough alone?