That's pretty cool. They used to sell something similar, with a beta fish in a container with a plant stuck in the top. The plant ate the fish poop and the fish was supposed to eat the roots. I think they lasted for a while, but it really wasn't a great idea because I don't think fish naturally eat roots.
It is pretty cool isn't it?
It seems a bit strange for a plant to eat fish poop and a fish to eat plant roots. But what do I know right?
With the eco prawns, they can reproduce and you can 'build' your own aquarium. Just go to the shop and buy the glass container and decorative items you like.