Firemouths can reach 6 inch or more and their attitudes match that of their cichlid nature in a tank that size you will have constant fighting. A 55 gallon is a nice size but rather small and very limiting to what you can keep. Do you know what a stream tank is? Hill stream loaches are very interesting and a 55 would make a great lifetime tank plus it would save your parents electricity cuz you would not need to run a heater in the tank.
