Normally my Beagle's first two stools of the day are pretty firm. But as the day goes on, his stools get progressively softer. By around 7:00pm, his stool is extremely soft. But then the next morning it is fine again. What might cause this variation throughout the day? I would think if his food didn't agree with him, his stool would be too soft all the time. He is on Innova Puppy food, about 1 cup twice per day. We've cut out any treats for now, so he is just eating his food and water.