Awe, I'm sorry to hear that. It's always hard to lose animals.Super nice duck pond! I have been trying to figure out how to do something like that in my backyard. Mine currently have access to a large stream which is fabulous; however, very dangerous predators depending on time of year. Last fall, lost two W Harlequines; 1 to a mink and then 1 to a bobcatIt was agonizing.
When I have a bit more time, may I contact you about the construction of your pond?
Happy Friday,
Lisa

I found a very detailed article about the construction of a duck pond, I will see if I can find it for you. That one was set up with a filter and is a much better design than ours.
The great thing about ours is it's fed by a natural spring, but late summer that slows down and the overflow does it no good. Also, we planted 3 trees in there and they've grown at an incredible rate. Sadly, the root systems head for the lovely fertilizer/water and have cracked the concrete...We're going to try and grout it this spring, but I imagine it's going to be a never ending problem.
So...maybe I can tell you what not to do?

Thanks for reaching out,
-Meg
And here is that article I mentioned! It's a long one, but lots of detail

https://www.tyrantfarms.com/how-to-build-a-backyard-pond-with-diy-biofilter/