It is way better to have more room than not enough. As long as there is a warm spot then it's fine. Ducks grow very quickly and after a few weeks the kid pool is going to be a tight fit.Those look similar to the setup I'm trying to perfect right now. Is there any downside to having such a big space (pool) for only three ducklings? I'm just worried about the enclosure keeping enough heat for them. They will be in a basement while they are young so I want to make sure it stays at the correct temp for the little gals!