Hey, everyone. I’m John McCoy, Production Manager here at G&D Chillers. We’re going to go over the proper glycol mixture for your system. G&D builds all of its chillers to run at a thirty-five percent glycol to sixty-five percent water mixture. That works out to 24.75 brix. Check your mixture using a refractometer. A hydrometer will not work. It will not give you an accurate reading. You take a little bit of your mixture, either from the reservoir, or from a purge valve, or a drain valve someplace. You want to put it right here on the spot. Flip it down. And when you look through it, it’s going to give you an accurate percentage or freezing point, which is ultimately what we’re checking for the mixture you have in your system. If you need a refractometer, G&D can help supply those for you. Contact Us