The bigger varieties you can. In this old video you can see my big 7" orange melanotaenia Trifaciata kept with South and Central american cichlids along with alot of other tank bruisers. I even had a softshell turtle with him at one time..
[video=youtube;jHYmCoTeY1k]https://www.youtube.com/watch?v=jHYmCoTeY1k[/video]