We all know how difficult it is to identify the sex of these fish, so please post a picture in here and we'll try to help you (or at least give an educated guess!).
I would say tha should definitely be a pair. I don't have any that are that furry in their back half, so now I'm kind of wondering if the one I have in a pot isn't just a dominant female or something. Mine are fat and sassy, but no spawning, the jerks! Hopefully yours will get the idea soon I'm just really not qualified to help sex these much yet, since I don't actually have any spawning going on!