Gu electro brew tablets gu electrolyte brew tablets are simple light tasting and natural they are invariably better than water alone and bring your system into balance more quickly by helping you retain more of the liquid you ingest whats in it not calories just 10 calories for an ultra light hydration drink formulated to help achieve electrolyte balance electrolytes an optimal blend of sodium and potassium to offer consistent hydration during activity stevia sweetened with a natura