Hi there,

I think the problem wit your female fish is may be due to a few reason:

1. It might have been infected by internal diseases for example infection on inside the digestive system, viral infection etc, which might be carried from the shop aquariums or the original habitat. Even if its pregnant now, if it manage to give birth, I don think the babies will be healthy based on my past experience. The best way is to isolate it out from other fish by putting in another small tank to avoid any disease to get to your fish.

2. Check fish skin, fins tails and other external features to check for any fungul, skin rot, or fin rot etc. If this is the case, can treat the fish the "green liquid" to treat it. If its fungal infection, treat it with the other liquid which you can get from the shop. Sorry, I forgot exactly wat's the name of those treatment liquids for fish. But since you bought the fish a month ago, I think it might be a bit late already.

Anyway, Eric, like I said before, u can isolate it from other fish and put in small aquarium. Another way is to put some salt in the tank where u put the female fish. A little bit will do. I don know how to explain to u on the effectiveness of the salt treatment becoz my fren never told me the theory, but I did try before on some of my fish when they were sick, and it able to treat 40% of them (the other 60% RIP). But if you r hardworking enough (Don b lazy like me), can surf in the net for ways to treat your sick fish.

(Tips: next time when u buy fish from the aquarium shop, if u see there's a lot of death fish in the tank, never buy it coz the fish might have died due to infections. If you like swordtails, always make sure the fish are active, fins are upward, stretched tail, solid belly and the eyes are not too dark when you choose them).

Regards