dFunction

Ducks using it now... And latest photo with roof planted, still to grow a bit...

Not yet, only just gone in... But it won't tip because it's anchored with weights that pull it down into the water so takes a bit of effort to get it to tip in any direction. Should easily take the weight of the ducks.

Floating on pond... Sits nice and steady. Yet to do green roof, will wait till frosts are over.

I've used polystyrene with plastic 5litre containers trapped in between. Does take a bit of trial and error with how heavy the construction is. Will be anchored with bricks and jobs a gooden!