I bought it as a filter for my turtle tank, pretty but not functional. A small powerhead can be enclosed with two filter pads on each side with a hose connected so the water comes out the front looking like a waterfall. It can and has been fully submerged makes beautiful decor. I had it with some cichlids and they loved it for hiding, without the top of courseWhat is that in the 2nd/3rd pic.
I bought it as a filter for my turtle tank, pretty but not functional.