Definately female lol. How big? She doesn't seem so huge yet. I bought a few in march 21, and the male I kept is already 8 inches, and I bought them all at .5 inches
Usually around 6 inches they can't live with any other fish anymore. Had mine with 2 convicts, a giant danio and a fremouth ( I know strange combination but the cichlids were small and the danio was supposed to get eaten) as soon as my jag got about 6 inches he killed everything but the female convict in one night. The female convict is never bothered even though she could be eaten in seconds, and like I've said, he's 8 inches now, yet he still doesn't bother her at all. But yea, managuenses at about 6" become crazy territorial (with my experience)
Hehe just wait till she is happy by herself. She'll lay eggs and attack EVERYTHING near them. I actually got rid of my first managuense because she would lay eggs, then I would disturb them and then she would be upset. I didn't want a mad fish all the time, so I got rid of her and bought 5 half inch babies, ended up keeping a male, which is quite a beauty in my opinion.