It's too tall, even if they flap and jump high enough to get in they can't get out because the soft set pool sides won't support them and slide back in. You would have to have the water less than 3 inches from the top at all times. They aren't like wild ducks that just take off and fly out of a lake. Ducks have problems with a ramp that is too steep and it would take a very long ramp to be the proper grade for them to be able to walk up it. I don't suggest it all.