Fish Pond "inverted aquarium" or a "bottomless fish tower

I made this fish pond myself and used my old aquarium in it. I placed four stones in the pond and set the aquarium upside down on top of them. Then, I sucked all the air out using a drip tube. The water from the pond started rising up, filling the aquarium completely. Now, the fish have started going from the pond up into the aquarium to enjoy the view outside, and they look very happy