Congratulations on the new ducks! To answer your question ducks need a pretty good amount of room. The thing that we have is a chicken tractor (But we call it our duck tractor.) It is basically a small duck house with a small door leading to a big pen. The house is predator safe so we lock them in there at night. The run is made of wood frames with chicken wire on the sides and mesh on the top. There is a door leading out of the run in case you would like to get in there. We only have three ducks but their house is about 3 by 5 and has 3 nest boxes extending out of the back. The pen or run as we call it is very big. I'm not quite sure how big that is but it is at least 11 by 5. The nice thing about the tractor though is that you can move it so the grass under does not get killed and the ducks have nonstop grass to wander through. Also you have the perk of pest control and free fertilization of your yard. We also put a small kitty pool in the pen for them to splash in. Beware though for they are very messy and the pool will need emptied and refilled every day. If you have any more questions feel more than free to ask me!