Don't forget how much waste 70,000 animals produce & the task of keeping the animals from killing each other.
“O ye of little faith”.
God brought the animals to the ark, two by two, seven by seven (from the bible). I’m sure they were not trying to kill each other then (angels leading them in)and I wouldn’t be surprised if angles had something to do with keeping the peace on the ark. The ark and everything on it were protected supernaturally. I don’t know about the waste but maybe Noah and his family threw it overboard? Food? Maybe some kind of supernatural hibernation? Just guessing But I would guess I’m not too far off.