The day prior to colonoscopy other the the 3 liters of water with the adequate solution what else can we eat?

Nothing: Usually the day before the colonoscopy, once you start drinking the solution, nothing other than clear liquids with the solution to clear out your lower GI tract for better images. Follow your doctors advice, but normally only clear liquids-broth, water, possibly jello.

Colonoscopy: The day prior to colonoscopy, you should not have solid foods. These are some items you are allowed to have: water, apple, white grape juice, broth, coffee or tea (without milk or creamer), clear carbonated beverages such as ginger ale or lemon-lime soda, gatorade or other sport drinks (not red or blue). You should have all these information in your instruction for the prep.