I would first try feeding him 1 cup twice a day before switching him to once a day feedings. Most members including myself feed our guys 1 cup of kibble in the am and 1 cup in the pm. Maybe 1 and 3/4 cups twice a day is too much food for him, and that's why he's leaving some of it. I'm just afraid feeding him once a day wouldn't be enough, plus feeding him once a day means hes only being fed once every 24 hours, which is a long time to go without food in between feedings. Some bullies throw up when they go a long time with an empty tummy. We also feed our guys Fromm's, and they have been eating 1 cup twice a day since they were 7 months old, they are 2 years old now, and both maintain a weight of 45 lbs.