I have kept tanks in Wi outside, but seasonally had to bring fish inside.
I would not try to keep tropical species outside in Georgia year round.
The country of Uruguay has a similar climate to southern Georgia, so there is a chance you could keep cichlids from that country outside.
Species such as Gymnogeophagus, or Australoheros, the can handle temps in the mid 50s, might have a chance.



Australoheros left, Gymnogeophagus, middle and right.
But as jjohnwm warned, if you have raccoons, certain snakes or other predators in your area, they can be a problem
I tried to keep Gymnos in a pond , but only until, and after I dug steep sides of over 2 ft in depth, I´d find half eaten dead cichlids in the morning.