The kid pools are flimsy and deeper than necessary. The water needs to go to the top edge for the ducks to be able to hop out ot else you need to offer steps or a ramp. I have found that the plastic kid sandboxes work better because the double walls make them more sturdy to flip them over to drain and clean them. They like the seats on the edge because they will stand on them and just scoop water with their bills in addition to using them to enter the water. I have one that looks like a treasure chest but this is the one I want once I can find some cheap used ones. I like the look of the stone sides.
The lid is nice if you want to keep them out of the water for any reason but we don't use the lid on ours much. It is nice to have during duck roundups, though, so the ducks are not jumping in the water when we want to catch them. We tend to lean it against the fence and then they nest under it but I have thought about making a frame so we can use it as a roof for an open shelter (for shade, mainly).