Alternative dog run but prefer flushable gravel one. Perfect Turf® Dog Runs No Muddy Paws! Much easier to maintain than natural grass. More gentle on your dog’s feet than gravel or mulch. Droppings become dry & hard making clean up a breeze!
The owners of this pen say that they really like the lobed-shape of their pool because the ducks can swim in their own areas. Based on their other photos, I don' think they have a drain, so they have to lift the whole thing out when they need to clean it.