Water intake varies by temperature. Typical rides in the 90s I'll drink a bottle of water every 10 to 15 miles. Maybe up to 25 when it's cooler. I have always drank lots of water, but since the radiation killed my salivary glands, I have to take swallows more frequently. I drink only water on short rides. On longer rides I'll have Gatorade or similar in one bottle and water in the other. I don't need anything to eat during a ride lest than two hours. On longer rides I like to stop every 20 to 30 miles to stretch, refill bottles and eat. I may snack on a Clif bar or fig Newtons while riding if the stops are infrequent. On organized rides with good rest stops, I usually just eat fruit, PB&J etc at the stops. I often supplement this with gels, especially on rides over 60 miles.
I used Perpetuem when I was having a hard time eating enough to keep me going, but I didn't like it and have not used it since.