Green terrors come from Western Ecuador, North of the Andes, they are not typical amazonian fish in their water requirements. in the natural range they can be found in quite hard water with a ph as high as 8.Therefore water chemistry should not be an issue.
However I do share Franks view on mixing them with Africans.It seams like an odd mix that I would not be happy with.
Still if it's working and your happy with the mix then I guess that's your call.
Definitely understand the viewpoints, just as some don't quite enjoy keeping hybrid cichlids. It's just a neat color scheme IMO with more movement in the tank! Stanzzz do you prefer gold or silver Saum? The silver one is starting to grow on me



