breeding swordtail fish

hello does anyone know how to breed swordtail fish my swordtail is really fat and black from the bottom please help thanks a lot

Hi what do you wanna know about them? Are you trying to ask if your swordtail is pregnant?
Usually the black thing that you we're talking about is called Gravid Spot only females have those and sometimes when they're pregnant they get really really black and gets bigger and one more thing they also get really huge like about to explode. Actually i got 1 Swordtail female at my 10 gallon tank i just separated her today because she has sign of giving birth around this week. not very soon. But it will keep her calm and not stressed before she gives birth. and also one of my swordtail female just gave birth on my Community tank good thing i have a little bit of floating and planted plants so the fry can hide.
Signs:
1. Lack of Appetite
2. Will gonna get a food like flakes then she will spit it out crushed and blended.
3. Always wanna be alone or always hide usually on plants, back of the heater, or filter hose.
4. She sits on the ground feeling really heavy.

Some swords doesn't really show signs they just pop it out like somewhere no one bugs him. Idk my potential preggy swordtail right now is acting very weird. I think she hates me.

thanks a lot i have my swordtail in a 10 gallon tank with a male hope they dont eat their babies

I see goodluck with the Frys. Anyways you can actually buy some Plants that are a dollar or two in a fish specialty store. i got mine in Sierra Fish and pets store down here in Renton. just ask any fish store about A bunch of plant that are good for livebearer frys.

One more thing if you got a Preggy fish and live with a male usually You will need 2 female per male fish so less stress on the preggy female or even she's not preggy. Fish get stressed too like us. but fish got a very bad kind of stress they usually die just because of stress. and just an info usually a fish that just gave birth gets stressed really bad too so whenever they gave birth breeders usually seperates the female specially if she is the only female.