How do you tell the difference from male to female in mollies?

Question

I have a mollie and gonna get another one how do I tell which is which so they can breed.

Answer 1

That is probably the main way to tell the difference between male and female. There is no size difference, and the only way to tell is to look behind the tail fin. If there is an organ that looks like a stick or straw, it is definitely a male. If it's only a fin, it's a female. The sex of the fry shouldn't be determined, because they all look like females in the beginning, and they either stay female, or change to male, time will tell. Females tend to choose mates that are smaller compared to themselves, and if you do plan to breed mollies, or any other live-bearing fish and want to in succession, always have more than one tank, so one can be a maternity ward, one can be a tank for babies, and so on. Babies need a tank that is at least 10 gallons, or they won't grow at a normal rate. Overcrowding is another problem since fish owners usually have numerous live-bearers of different species.

Answer 2

On the bottom of the fish, back toward the tail, the female will have a rounded fin and the male will have a straight - "stick looking" fin.

Answer 3

male live bearer have what is called a gonopodium...an extention of the anal fin, this is visible in even young fish.

http://www.flickr.com/photos/ianlloyd/with/125961148/

here is a site with pics, click on pics to enlarge to see better.

Answer 4

A good indication would be makeup, is it wearing a bra, high heals???