Gosh that is a tough one. I have two babies too, but I am lucky they are both chow hounds. They clean their bowls within 5-6 min. I do stay with them and monitor them, if I don't Jada gets finished before Bogie and she tries to get in his food.
It would be hard for you since one of your babies is more of a nibbler and eats throughout the day and the other one is like my two, loves to eat. I am sure you will get some more input for members who have the same situation.
Love the pic, you have two little cutie patootie's.