It’s about 5 feet in diameter and a good 8 inches deep. So, theoretically they could swim (by swim, I mean they lie flat and zoom across the pool and do barrel rolls). They like to do that before splashing around in it and grooming.
Often when I change things up for them, I have to show them where, how and what they need to do. So I filled the pool and grabbed the ducks and put them in it. They freaked out and flew out of it, in their domestic duck kinda way (lots of scrambling). I thought maybe the just needed some time, but nothing I did enticed them to stay and play.
It was freaking them out. I spray painted them dark blue and filled the pool. They no longer freak out.
But now it’s a matter of the sides being too high for them to get in and out easily. I’m working on that with a ramp, but they aren’t thrilled, so it may be a dog pool this summer and the ducks will be happy with their old baby pool.