The area at the base of the stomach is called the egg spot - it'll be very dark, even black, if the fish is pregnant. Same deal for platys and mollys, they are also both livebearers.
If you want to keep the fry, you need to separate the mother out of the main tank into a net, and once she's dropped the fry, put her back into the main tank. Guppies have no problem at all eating the babies! Once the fry are big enough to not fit in an adult guppy's mouth, you can re-introduce them to the main tank.
If you want to keep the fry, you need to separate the mother out of the main tank into a net, and once she's dropped the fry, put her back into the main tank. Guppies have no problem at all eating the babies! Once the fry are big enough to not fit in an adult guppy's mouth, you can re-introduce them to the main tank.
