Yes, last summer my ducks went 12 to 14 hours no food or water. Its worth noting its not hot where i live so dont have your ducks lock in a 90 degree shed with no water.
If there is no mold or ammonia smell then its working for you. If you have no problem letting them in and out every day then there is no reason to have food or water in the house. Besides the obvious water splashing, the food that they eat all night gets pooped out before they come out in the...