Instructions
Isolate your female mollies so you can examine them one by one. Place the female mollie in a fish tank away from the males, with other females or by itself. Note that the female tails are fan shaped while the male tales are more elongated.
Examine the female mollie's belly for a black spot. This black spot will grow as the babies grow and indicates that the mollie is pregnant.
Watch the mollie for signs that the black spot is growing and that her stomach area is getting huge. Place the mollie in a breeding net when the black spot is clearly visible so the babies will be born in the net. A mollie can have between 12 and 100 live babies at a time.
How to Tell When a Mollie Is Ready to Give Birth
Mollies are simple fish to keep alive and will breed in a variety of conditions, which makes them perfect for the first time fish keeper. A mollie that has bred will usually produce its young in about 30 days after the breeding takes place. You can help the mother by feeding it plenty of mollie fish food and protect the fry by placing them in a breeding net or a separate tank away from other fish.