I had a 35 gallon freshwater hex tank in high school... 20+ years ago. It was an aggressive tank.... Green Terror, Wolf Fish, Florida Gar, Black Tip Piranha, some type of Bass, a snakehead, tiny Green Spot Puffer, and a few other African Cichlids that I converted from brackish to fresh. It gave me the foundation for keeping saltwater.
My love has always been the fish, not plants or corals. So soon after, I traded my fish in for credit at the LFS and switched to saltwater. It was another predator tank that was heavily stocked with Triggers, Puffers, Groupers, Lion Fish, Long Horned Cowfish, Harlequin Tuskfish, ect...
Back then there wasn't really much info on how big these fish got. They stayed in a 72 Bow tank and people used to say that the fish grew to the size of the tank back then.