That is a good idea, but I don't think my fish would live very long without water.
I want to have a working aquarium with live fish in it along with the playmobil. I kept up an aquarium for years, and it's a LOT of work, all the algae can be aggravating, plus changing filters, siphoning the gravel, partial water changes, water treatments, trying to keep the temperature just right, but I still love it!
However that is a good idea and I may set up a dry aquarium for a while if I have trouble finding time for a real aquarium. They are time-consuming, and I'm a lot busier than I was last time I had one, when I was a teenager.