Terrific idea to use a juice fast to reset your body chemistry. Since so many folks with mood disorders are deficient in Omega-3 fatty acids, consider adding some omega-3 fats to the fast.
This violates the "purity" of the fast, but it helps utilize the nutrients in the juices better. For instance, Beta Carotene needs to be eaten with some fat to assimlate properly. Same with other fat soluble vitamins.
I mix 1/4 cup fresh ground flax seed into my juice and add a couple tablespoons of lecithin as well. The lecitin helps emulsify the fat and juice. The fiber in the flax helps me "go", but one could use flax oil instead.
I make a thermos and take it to the office to drink small amounts throughout the day. Keeps me going, energized and happy. I especially like the green veggie juices, including broccoli, cabbage and kale. I mix them with lemon, and ginger or garlic to add some kick. Then I sweeten the mix with apple. When I drink it, I dilute to taste with filtered water.