swordtail breeding..

Question
I have noticed that my female swordtail has grown quite a belly and was wondering what other characteristics would she have that I could tell whether or not she is really pregnant? During my research online, I found a site that spoke of swordtail guppies, with no real info, just pics and I have noticed that my guppy spends a lot more time with her than the male swortail. Is it really possible that she could be pregnant by the guppy and what's the likelyhood of that? If she does have the babies, should I take them out away from her so that she or the other fish wont eat them?  I have all community fish and a rope fish (that stays very calm and quiet and to himself).  Thank you for your time and advice!!!

Answer
Hi Mandy;

Swordtail guppies are simply a strain of guppy that has a swordlike tail. They aren't a crossbreed of the livebearer known as the swordtail and the guppy.

Your male sword only needed a moment to breed with her and we don't always see it happen. Quick little fellas! If the male guppy is a bit sassy he may just be keeping the male sword at bay because he lacks females of his own. Livebearing fish can also have babies for several months from one incidence of breeding. So, even if you had no male in there of any kind she could still have babies for 6 months or more. Weird, but it works for them I guess.

It is best to separate the baby fish right away. You are quite right about them being eaten. The ropefish would be the first one to go hunting. Baby fish are their favorite food. Yikes! Most baby fish are okay in community tanks with plants and other hiding places but not with a ropefish in the tank. He could even slither up over the edge of a breeder net or trap at night and eat all of them in there. He would then slither on out again with a full belly and a smile, and you would never know.

I wouldn't use any tank smaller than a 10 gallon tank for the babies. They will grow and need plenty of room, plenty of food and frequent water changes to thrive. A bare tank with no gravel, just a heater and sponge filter hooked to an air pump will do quite nicely. They eat a lot and food can get trapped in the gravel so it is more sanitary to avoid using gravel in baby tanks. If you aren't able to save the first batch, there will be more. They have babies every 4 to 8 weeks usually. Here is more about raising livebearer "fry" (another name for newborn baby fish);

http://www.atchison.com/fishinformation/breedinglivebearers.htm#Fry

Have Fun!

At Your Service;
Chris Robbins