It's hard to imagine big heavy stumps floating, but trust me, they do frown. I tried to anchor mine, but even before they were submerged, one broke free and floated like a cork. Me and kid #1 had to canoe out to it and tie it off to the top of one that stayed anchored so it wouldn't float off and sink where I didn't want it. Took a month or more, but eventually soaked enough water and sank.

Very exciting waiting for a pond to fill. I bet it'll look great. Please keep us updated!