I five of these myself, two males and three females. The males will gape at each other and the females will get pushy. I have the smaller pair seperate in hopes of fry. The other three are in with betta pictas, and I have had them with rasboras, killies, domestic bettas, all kinds of other fish with no issues. My larger male even adopted some endler fry i was hoping he would nom.
Binbin, do you have any contact info for the person your getting some from? I need new blood in my lines in the hopes of viable fry.