Every summer when I visit my family in Brazil I eat plenty of fish commonly kept in aquariums. They are of course wild caught fish (I wouldn't eat a fish out of an aquarium). I've eaten RTC, TSN, pacus/ tambaqui, geophagus brasilensis, tilapia, Ageneiosus valenciennesi (not sure of English name for this fish), wolf fish, and even piranha stew.
Pacus/ tambaqui and geos taste like dirt. The catfish is really good as is wolf fish. Wolf fish has a lot of tiny bones though. I wasn't a fan of the piranha stew, it was prepared in the middle of the pantanal Forrest so maybe it would be better in a restaurant.