I drink about three liters a day for temps into the 70's and reaching camp by about 5 PM. Liter #1 by noon, liter #2 by 5 PM, liter #3 used for evening meal and the rest drank the next AM. After reaching camp, if by around 5 PM, I only use 1 cup of liter #3 for my meal so I am not up at night peeing. For hotter weather, I may add another liter during the day.

Drinking over a set period of time is more effective for complete rehydration. Rapid replacement (cameling up only at water sources with little drinking otherwise) of fluid stimulates increased urine production and reduces body water retention.

Store bought electrolyte powders are overly expensive and mostly useful for competition (when you may not eat solid foods) since you get those electrolytes in your meals/snacks.