The owners says:
It’s a little bigger than it looks in the video but I thought the same thing. It’s a pro build in what was supposed to be an oversized planter. They said they will only grow as big as the area allows, so they will just be smaller. It has a good steady current so it simulates a creek. There are some big caves in there too to give the fish some calm spots as well. I’ve had salt water reef tanks in the past but never a pond. I forgot how much I miss waterscapes.