We thought it was the waterfall, so we adjusted the hose. And woke up Tuesday morning to an empty pond and a huge bubble of water under the pond. So we got it out on Wednesday, got it dried (kitty litter does the trick), and back in on Thursday. And thankfully, Friday morning we still had water in the pond! Apparently the waterfall was right on the edge rather than overhanging just enough to not cause issues. Go figure.
So I added these plants yesterday; a local nursery had a bunch of their water plants on sale (75% off!), and so, of course, I had to get some. From everything I've read about the ones I got (2 hardy water lilies, a pickerelweed, and a Louisiana iris), they'll overwinter fine in our pond as long as the water doesn't freeze. Since we have the waterfall, that shouldn't be an issue. Especially in our zone.
So, now I've been driving Phil crazy looking up fish I can put in the pond come spring. It's too small for koi (which makes me a little sad) but large enough for several different goldfish species. I just have to figure out a way to protect the water lilies. I'm thinking about putting some type of netting cage over the pots about 6 or so inches so the new growth is protected from nibblers but the plants can still grow and expand. Not sure what to do yet, but I have a while to think about it.
Here's a video of it. Doesn't it sound great?