I use the same stock tank as my koi pond. Don't have to worry about raccoons shedding this on. Had deer fall into it once or twice. They made it back out, but surely got scarred. It is incredible how sturdy it is and it can withstand strong freezing winters. Our tank is set into the soil...
I like that one. Lots of work put into it. Spoiled duckies for sure. Why do you have netting hanging on top? Is that for extra shade? Also do your ducks pick up the rocks and dump them into the pond? I have rocks like that under my dogs water bowl and my ducks pick them up and dump them...