I have 2 black molly's, and I don't know whether they are male or female. can anyone help me to determine what they are? I also have a female fancy guppy and I have no idea how to tell whether or not she is pregnant. can anyone help me?
From what I read the Male Molly has a L shaped rod fin on his anal area (under belly), the female does not. I do not have a picture to show you but there may be someone who has Mollies on this forum who might.
Yes, they need to be kept in trios with one male and 2 (or more) females. Otherwise the male will chase the single female relentlessly. With more than one girl he has to divide his attention.
As for being preggy, she will just get insanely fat. ;D But, like leafgirl said, if she is with a male she will get pregnant.