I use a vinegar solution of one part vinegar to ten parts water. I let it soak for about half an hour. I would love to purchase more organic produce, but that is hard on the budget.
The first few times you do this you might be surprised by the cloudy water and stuff floating in it. Especially grapes. Using this solution helps to prolong the life and prevent molding of grapes and berries.
Another perk to cleaning all of your produce at once is that you can go ahead and prep it. Grapes don't last long around here so I pull them off of the vine. The littles snack on them often.
I find that if I go ahead and clean and slice carrots I am more likely to snack on them. There is not always time during the day to stop and peel and slice a carrot. Having everything clean and ready for use helps us to eat more fruits and veggies.
May your day be filled with joy and contentment!