SA habitat, not as simple as we think

[neutrino]

Many of us started out accepting a common belief in the hobby: South America means warm, soft, low pH water and that's what your fish need. This is continually reinforced in the minds of many by a preponderance of forum posts as well as some hobbyist literature.

However, this is not only incorrect but illogical. South America is a large and diverse continent, latitude, altitude, geographically. and geologically. So the next step for some of us was to learn about the three basic river types, blackwater, clear water, and white water and how physical and chemical parameters differ between them. Okay, many of you know this, but I bring it up to introduce this:

Even that classification, dating to the 1950s (or centuries earlier if you include traditional native wisdom), turns out to be a bit simplistic:

https://www.witpress.com/Secure/eli...XHB8DUsuuHIxx69PPn96ouIp5x9r_QYDBqY5aDSopXcI4

 

[duanes]

Although they focus on the Amazon basin in the study above , water condition west of the Andes, and in southern South America are even more diverse.
West of the Andes water parameters tend to be more alkaline, and with snow melts in the Andes, keeps average temps down..
And southern South American gets quite cold, even gets snow, so the cichlids of southern Brazil, like those of the braziliensus complex get seasonal changes and cooler water, and those from Uruguay and Argentina like Gymngeophagus, Australoheros, and some Crenicichla may not be considered tropical species at all, but sub tropical, or even temperate species requiring cool downs.

Gymnogeophagus above.
I kept my southern South Americans in tanks without heaters, in hard, highpH, high conductivity water, and they lived quite well, spawned, and showed best color and health after cool downs with water temps dropping into the 50s F.

 

[neutrino]

True. Another thing of note in the paper is a tributary or feeder stream can be different from the main river, sometimes considerably. So a fish listed as from Tapajos, Tocantins, or whatever, but actually collected a mile or two upstream from the main river can live in different water conditions than we think. Fortunately, most species are adaptable and forgiving-- within reason. In fact, the same species may encounter different conditions over its range and the specifics for some species or locations can be difficult to ascertain, or incorrect in common descriptions from some sources.