Another SA species (7 1/4 lbs) that is also suffering horribly from the conditions in the S. Florida canals. lol
In their natural habitat, most SA species have to contend with a very hot, dry season, and a very wet, and much cooler, rainy season. It is in the latter that they travel into the shallow floodplains of the Amazon and breed. I don't know what the exact temp fluctuations are, but they would be very similar overall to what a CA species such as Amphilophus would experience in its native habitat.
There are MILLIONS of oscars, peacock bass, etc caught each year in Florida lakes, ponds, canals, and the Everglades. These SA species have apparently adapted quite well.