You misunderstood me. What I ment by my comment was that I've always envisioned a set up where they were able to jump (since that do that quite a bit in the wild) but be safe. My idea although a little different from yours would go something like this - I would make a pond with a viewing window that is completly enclosed (the hang up here in my vision is maintance) without ledges where the wall meets the pond and has some branches suspended randomly over the water where I could put in some bugs for them to hunt.
It didn't even cross my mind that they would be big enough to be able to make it over your barrier...
