I'm doing a 10 week challenge at my gym (in week 6 now) and they want us to shoot for 1 gallon a day. I've only been able to do that 2 or 3 times, its very difficult! Right now I've been consistently doing around 96 oz daily during the week and 32-64oz on weekends. The two biggest differences I've noticed so far is my skin doesn't get "ashy" if I don't apply a moisturizer and my nails and cuticles look so much healthier and the skin around the nails not as dry, which I've been trying for at least 2 years now to get them to not be so dry by moisturizing the heck out of them with hand creams and cuticle oils. Who knew the solution the whole time was increasing my water intake, problem solved!