Just to give you an idea, I have a comunity tank that I have thrown a mix into which include:
SJD,s Black ghost knife
Albino gerdneri Gunters fire killi
Dageti Kortause killi
palmqvesti American flag fish
guppys neons
white clouds Hoplo's
Bristle nose Australe gold's
I think that is about it. But do note I only add males due to identifying the species.
It makes a great looking tank and always gets comments.
cheers