What could we keep in our Tank?

well if you can get a small heater and filter you could keep a betta fish in there,or maybe a dwarf frog or 2,or you could go with maybe a dwarf hamster or a pair of mice,though they would need some time out of the tank to get exercise, or you could put in a small wheel. possibly a giant african land snail, i wouldnt put anything like syrian hamster in there as its to small,hope you find a new pet soon x