Symptoms of Pregnant Molly Fish about to Give Birth
There are various stages in Molly fish pregnancy. If you are a new Aquarist or if you want to breed Molly fish you must know about Molly fish pregnancy stages. So, that the parent fish and fry remain healthy. After reading this article you will definitely get all the information about Molly fish pregnancy stages.
Breeding Molly Fish
Breeding Molly fish is not difficult even for new Aquarist. Breeding in Molly fish is different from other fish as they do not lay eggs. Instead Molly fish give birth to live babies called fry. Male mollies fertilize the eggs inside the female Molly’s belly. Female Molly fish can store the sperm and because of this without mating female Mollies can continue giving birth.

Molly fish’s pregnancy cycle lasts between 40 to 70 days. If you have both male and female mollies in your aquarium or fish tank then they will mate naturally. You will find a lot of fries in your tank but these fries cannot live long because adult mollies eat these fries right after their birth. So, if you want to breed Molly fish and want to keep baby fries safe you should know some important things.
- Molly fish pregnancy stages
- Your molly fish is pregnant or not
- When your Molly fish is near to giving birth
- Caring for Molly’s fish and fries before and after birth
What are the Molly Fish Pregnancy Stages?
Molly fish pregnancy consists of various stages which are as follows:
1. Conception
If you have male and female mollies in your aquarium or fish tank conception is easy. The male Molly fish mate with the female Molly fish and transfer a substance called milt which contains sperms inside the female Molly fish. In other words male Molly fertilizes the eggs inside the female Molly’s belly.
2. Formation of the Embryo
After 7 days of conception or fertilization, the eggs begin to form an embryo. The Gravid spot is also a little prominent.
3. Development of Fry
As the pregnancy advances the embryo develops into fry. As the fry grows inside the Molly fish belly the size of the Molly fish belly increases. The Gravid spot becomes darker and with the increase in the size of Molly’s fish belly, the Gravid spot becomes larger.
4. Pre-birth Stage
At this stage, the Molly fish is ready to give birth. The fry is fully developed if you look closely around the Gravid spot you can see the eyes of the fry from Molly’s fish belly. This is the time when Molly’s fish belly is swollen and square-shaped.
5. Delivering Fry
This is the stage when Molly fish delivers live fry. If you want to breed Molly fish you should separate fries from adult mollies because adult mollies consider them as food and eat them.
What are the Molly Fish Pregnancy Signs?
If you want to breed Molly fish it is very important to know about the signs of pregnancy then you will timely prepare for the best environment for Molly fish. So the mother Molly and baby fries both will be healthy.
1. Squared Belly
Female mollies have round bellies. When the pregnancy advances in Molly fish the size of its belly increases. When Molly fish is ready or near birthing at that time molly’s fish belly becomes square shaped as too many fries are inside its belly.

2. Behavioural Changes
Like human beings, Molly fish also have mood swings during pregnancy. When a Molly fish is pregnant it becomes overprotective. Molly does not like aggressive tank mates. Molly fish like to hide. It spends most of its time hidden in plants and aquarium or fish tank decorations. Molly fish like dark places during pregnancy.
When you see that your Molly fish is pregnant it is good to prepare a separate aquarium or fish tank for her. If you do not have a place or you do not want to prepare a separate aquarium or fish tank, then put some more live plants in your aquarium or fish tank.
3. Changes in Gravid spot
All female mollies have Gravid spots. A gravid spot is present near the anal fin on the lower part of Molly fish’s abdomen. If your Molly fish is of light color then you can easily find Gravid spots. However, if you have a dark color like black mollies or Dalmation mollies then it is difficult to find a Gravid spot.

As Molly’s fish pregnancy advances the Gravid spot becomes darker. With the increase in the size of Molly’s fish belly, the size of the Gravid spot also increases. So, we can say that when the pregnancy advances in Molly fish Gravid’s spot becomes darker and larger.
4. Increased Appetite
Another sign of Molly fish pregnancy is that the appetite of Molly fish increases. Molly fish needs lots of energy for the fries to grow and deliver at the proper time. So, you will see that Molly fish is very active at feeding time. It will also compete with other tank mates.
If you want to keep your Molly fish and fries healthy. You should visit a Vet and discuss proper healthy and nutritious food for your pregnant Molly fish.
5. Likes Warm Temperatures
Molly fish like warm water temperature especially when it is pregnant. If you will observe Molly fish you will see that it is swimming near the heating or near the lights of the Aquarium or fish tank. So, it is important for healthy mollies and fries to maintain warm temperatures in aquariums or fish tanks. If you want your Molly fish to be free of stress especially when she is pregnant then you should provide her proper environment that includes temperature maintenance.

Related post: Why is my Molly Turning Black?
What are the Molly Fish Birth Signs?
For a new Aquarist or for a person who likes mollies and wants to breed them it is important to know about Molly fish pregnancy stages, pregnancy signs, and last but not least the time of delivery. When Molly fish is ready to give birth it shows some physical and behavioral signs which are as follows
1. Appetite loss
At the start of pregnancy Molly’s fish’s appetite increases but when it is near to giving birth, Molly’s fish loses its appetite. Molly fish reduce their appetite or stop eating. It will ignore the feeding time hiding in the plants or aquarium decorations.
2. Changes in Gravid spot
When the Molly fish is in the pregnancy stage when the birthing time is near the Gravid spot becomes darker and larger. If you look closely around the Gravid spot you can see fry eyes.

3. Shaking of Tail and Trembling
When the water of the aquarium or fish tank is too acidic Molly fish shakes its tail or its body trembles. However when the birthing time of Molly fish pregnancy stage is near because of stress Molly fish starts trembling and shaking its tail.
4. Behavioural Changes
When Molly fish is near to giving birth it shows some behavioral changes. Most of the time it hides in plants and decorations of Aquariums or fish tanks. It will stay away or ignore all fish. Molly fish does not like aggressive tank mates. So, try to put fish species that are not aggressive.
The Bottom Line on Pregnant Molly Fish about to Give Birth
After reading this article either you are a new Aquarist or you want to breed mollies, in both cases you have sufficient knowledge. Mollies are happy to fish that are easy to handle. You don’t have to put in a lot of effort. Only some important things you must know and remember. An increase in appetite, increase in belly size, dark Gravid spot, aggressive or protective behavior, and craving for warmth are signs of pregnancy
Loss of appetite, very darker and large Gravid spot, always hiding, ignoring feed, staying hidden in dark places, and shaking tail are signs of being ready to give birth.
Conception, formation of the embryo, development of Fry, pre-birth stage, and delivery stage are stages of pregnancy. Best of luck to you and your Molly fish.