Swordtail Gender Change

[insecurity]

I've read that Swordtails, and some other livebearers can start out life as females, but can later develop into males. The saddest part of this process however, is that the converted males are sterile, meaning that they cannot breed.

I've had one female swordtail do this to me. I looked at my fish today, and I noticed that one of the females has developed the gonopodium- the livebearer's breeding organ, signalling that it is a male. Is it something that I'm doing as an owner that is resulting in this, or are the fish I end up with genetically flawed, therefore resulting in this blunder?

Any advice would be appreciated, as I don't really want to end up with a tank full of male swordtails.

 

[Cafrye]

Years ago I had a female swordtail that had lost her mate and a couple months later she began to cange to male...