Do Molly Fish Give Live Birth? Find Out Here!

Molly fish are a prevalent choice for many aquarists to start a breeding tank. These wonderful aquarium pets are one of the easiest fish to keep in the tank and breed without much hassle. But, one day, you will suddenly find little fry swimming in the tank, and you will have no idea when and how the whole molly breeding cycle started and ended. How do they even reproduce? Do these fish lay eggs in the tank? Or, does Molly fish give live birth?

Molly fish is a live-bearing fish, so yes, they will give live birth to the young ones. After a gestation period of 60 days, these mollies will give birth to nearly 10 to 60 live fry every time they give birth. But you need to separate the parent molly fish and live fry because molly fish will eat up their babies.

You are responsible for caring for the molly fish and its fry as both are equally vulnerable and weak for the first days. Therefore, make sure to maintain the water parameters and dietary needs to optimum. It is better to stay prepared because not all fry will make it to adulthood, and you will lose some of them.

I know this information won’t take you anywhere; the more we learn, the more we want to explore molly fish giving live birth in the tank. So, in this article, I will talk about the reproduction process in Mollies and how you need to take care of the fry.

Let’s dive in!

Do Molly Fish Give Live Birth?

Yes, molly fish give live birth to nearly 10 to 60 babies depending on the care level you are giving them. These fish are one of the most amazing fish to breed in the tank, and their reproduction process is very simple for you to understand.

Molly fish is a livebearing fish in the wild; hence they will not just turn up as egg-laying ones when you put them in an aquarium.

They will fertilize their eggs internally when the male molly releases the sperm. But, you know, the wonderful thing about female mollies is that they can store sperm for months.

Things To Consider To Make Molly Fish Safe After They Give Birth

There are higher chances of Molly fish dying after they give birth. Therefore, it would be best to take care of Molly fish when they give birth because it is a fragile time for them, and there are higher chances that your Molly fish might die. Molly Fish dying is bad, so you better take care of them.

  • Make your tank clean and healthy for Molly Fish.
  • Molly needs enough space in her tank because she will be a weak post-delivery process.
  • Change the water of Molly’s tank.
  • Feed Molly fish fresh food and be attentive to their diet.
  • Give Molly a small piece of shrimp or fish so she can eat it and satisfy her hunger.
  • Keep an eye on Molly Fish’s birth process because if problems arise, you might have to intervene in the process to save your molly.
  • Molly has babies under gravel or behind rocks or plants, so make sure to maintain that kind of atmosphere for them.
  • You can also use an antibiotic to ensure Molly doesn’t get infections.

If you do the above things, your Molly fish will be safe after her live birth.

Molly Fish Breeding Behaviour: How Do Molly Fish Reproduce?

You need to understand the whole process of breeding a molly fish in the tank environment.

You cannot just wake up one and choose to breed them, now can you? There is a certain period, a season when your mollies are all about mating and breeding.

So, make sure to keep an eye on the molly fish activity once in a while. But first, let me tell you about a male and female molly ratio in the tank.

You always have to keep at least 3 to 4 female mollies for each male molly. So don’t even think about two male molly fish in the tank without making sure there is enough female to balance the ratio.

Now, How Do Molly Fish Mate?

Your mollies are prolific breeders; hence the male has to impress the female and woo her to mate with him. He will spend a lot of time around females to pursue her while making sure no other male will enter her premises.

These male mollies will start to chase female mollies for mating purposes. Females will run away for a while and give in once she becomes plump with eggs and ready to fertilize.

Once the male succeeds in wooing the female, the mating process starts. Mating is all about transferring milt, a fluid that carries all the sperm with the help of gonopodium into the female body.

But what is gonopodium in fish? It is an anal fin in the shape of a rod which is more special than any other anal fin. Male molly will release the sperm while female molly stores sperm and fertilizes the eggs internally.

Do you want to know another wonderful thing about this? Your female mollies can store sperm for so long that you might even witness her giving birth after six months of mating with the male molly.

Do Mollies Pair For Life?

Most of the pairing will only last until the male transfers the milt into the female body; then, their relationship is quite over.

Sorry to say, but your molly fish won’t and don’t pair for life. However, your male molly will mate with any other female he can find and even try to woo the already fertilized ones.

So, in the world of molly fish, male molly is a casanova who doesn’t mind keeping too many females around and even tries to snitch the ones from other males.

And neither makes the female mind; she will store the sperm she receives for nearly six months. Then, when she is done with her sperms, she will give in to another male present in the tank chasing her now.

What Happens When Molly Fish Gives Live Birth?

Well, isn’t it given about the fact that you will start to see molly babies in the tank? This is because Molly fish will release the babies into the tank once they are hatched internally after 60 days.

At this point, your female fish will get weaker and weaker as pregnancy can take a toll on any living being. So she is quite vulnerable, and any changes in the tank will affect her and the babies she just delivered.

You need to ensure the safety of both parent molly and the babies in the tank and make sure no other fish bothers them.

Molly fish can die easily after pregnancy due to the weaker immune system and energy loss during the delivery.

Also, you need to separate the molly fry from the main tank if the female accidently gives birth to them there.

Other fish will eat up those small fry and their own parents will consider them snacks and munch on them as soon as they drop in the aquarium.

So, I suggest you separate the pregnant molly fish from the main tank beforehand and remove her from the fry tank as soon as she gives birth.

How To Tell Molly Fish Is Pregnant?

We all are eager to find out whether your fish is pregnant. Oh, I remember the first time I missed the pregnancy phase of the molly and only found out she was expecting when I saw small mollies swimming in the tank.

I lost most of them within a few days as I was unaware of the fact that molly fish eat their babies. So, let bygones be bygones, and here I will tell you all the tell-tale signs that your molly fish is expecting so you don’t miss a thing.

Sign 1: She Has A Huge Appetite 

If you female molly fish eating more than usual, then there is a chance that she is eating for more than one individual. If you care to look closely at fish’s eating habits before and after pregnancy, you will start to notice the change within days.

Sign 2: Squared And Plumper Belly

Most mollies have rounder bellies from the beginning of their life, but that doesn’t mean all of them. They probably carry babies now if you start to see female mollies getting squared off or rounder than usual.

The belly area will get thicker and square when fry develops inside her. But I have to warn you, look at other signs before deciding and concluding they are pregnant.

Sometimes, overfeeding, obesity, or swim bladder disorder in molly fish can result in the growth of the belly area. Test the water and other signs to ascertain your molly fish condition and know if mollies are really pregnant or just fat.

Sign 3: Visible Black Lines

Once you think that the belly area is plumper and squared than usual, try to catch a glimpse of black lines and dots near the anal vent.

Those black lines or dots are quite evident as those are the babies your molly fish is carrying. This is the biggest tell-tale sign of all time.

Gestation Period Of Molly Fish: How Long Do Molly Fish Stay Pregnant?

Now, I know patience can run thin when you have to wait for too long just to see the glimpse of molly babies in the tank.

And if you find out they are pregnant in the first days, the birthing process seems too far ahead and will never come.

This is because molly fish stays pregnant for nearly 40-60 days after a few days of the mating process. So, the long gestation period of molly fish can make you suffer from all the curiosity and suspense.

Don’t worry; the fertilization, the development of fry, and the birthing process can take time; you don’t want to have molly babies missing a fin or two, now do you?

Signs That Molly Fish Is Going To Give Birth

I know that once you find out about the pregnancy, the eagerness, curiosity, and excitement to meet the babies is too high.

But we often miss that moment and later discover a tank full of molly fry while the parent molly is busy eating its baby.

So, let me help you here. I will list all the signs that convey molly fish is going to give birth below:

  1. She stays motionless or swims less than she usually does.
  2. Loss of appetite is quite common. She will eat more during pregnancy but abruptly stops when she is about to give birth.
  3. You will have a hard time finding your pregnant molly. This is because female mollies prefer to hide in the darker parts of the tank, behind plants, rocks, etc., to give birth.
  4. She is more aggressive than usual.

How Many Fry Do Mollies Give Birth To?

Well, it entirely depends on the age, water conditions, eggs, sperm count, and immune system of the molly fish.

Your moly fish can give birth to nearly 10 to 60 molly babies at one time. The fry count may increase or decrease according to the health condition and egg development and fertilization process of female molly fish.

There are instances when female mollies have given birth to nearly 60-65 fry, but there are also times when the number is down to 15 fry.

So, you can never have entire confirmation about the fact that the mollies will have exactly these many fry this time.

And, remember, each fry is nearly a half-inch in size, so you need to plan the ideal tank size for mollies accordingly.

Hope for the best and maintain all the living conditions for the molly parent and the fry. It would help if you separated the molly fish from the babies as soon as she was done giving birth.

You might not know this, but the greatest enemy of molly babies is the one that gave birth to them. Molly fish are omnivores; hence she will eat up anything that can fit inside her mouth, even her own babies.

Do Molly Fish Give Birth At Night?

Yes, molly fish do give birth at night. This is also one of the reasons why you will barely catch molly fish dropping babies in the tank.

I guess it is an indirect way for female mollies to give babies a chance at survival. Don’t even think about keeping the lights on at night when your molly fish is pregnant.

She prefers to give birth at night in pitch darkness, so let her have it. Your molly fish might eat up her babies in a well-lit environment but not immediately after giving birth when she can’t even see them properly.

And, this doesn’t mean mollies will not deliver fry during the daytime. It is just a matter of preference among mollies; if she is ready to let go of babies from her belly, she will do it without looking at the sun or the clock.

But make sure to remove female molly from the fry tank as soon as she gives birth to all of them. Keeping pregnant mollies separate is as important as separating parent molly and fry almost immediately.

Do Mollies Give Birth All At Once?

No, molly fish doesn’t give birth to all the babies at once. Can you imagine nearly 10 to 60 fry coming out of molly at once?

There is an interval of some minutes or seconds between the first and every other birth. Your molly will burst if she even tries to give birth all at once.

Laying eggs all at once is simpler because the eggs are way small and can form a cluster. But for livebearing fish, it is a nightmare.

Each fry is nearly a half-inch in size, meaning it will be harder for molly even to let one fry out at one time, let alone 60 altogether.

How Often Do Molly Fish Give Birth?

Molly fish will give birth every 30 days to 40 days while having a gestation period of 60 days. These mollies will store sperm and fertilize the eggs every month if they feel like it.

You have to wait for 60 days to see molly babies in the tank. Please don’t get confused when you start to see molly babies even when there is no male present in the tank; female molly will only need male molly once to release sperm which she will store for another few births.

You can even find female molly giving birth to new fry even when her last encounter with male molly was nearly six months ago.

Where Do Molly Fish Give Birth?

It depends on the type of tank you have. If you have a tank with only a breeder box available, she will most definitely think of it as her hiding space and give birth near it.

But most of the time, molly fish will find a cozy environment near rocks, caves, plants, or other decorations to deliver babies.

Remember, your molly fish needs live plants in the tank for various purposes, and giving birth is one. Therefore, maintaining the proper environment for molly fish to give birth to their babies is necessary.

Molly baby cannot survive in the main tank among many predators, so separate them immediately, or just place the mother molly in a different tank as soon as you find out she is pregnant.

How Long Does It Take for Molly Fish To Give Birth?

The entire process will take between 30 to 60 minutes, depending on how many fry the Molly is carrying and how developed they are when they’re born. However, it is much faster if there aren’t many Molly fish in the tank.

Your molly fish babies will need you to take care of them in the tank. Ensure the fry tank has a good filter as molly’s baby will need well-filtrate water without a hint of ammonia or any other chemicals.

But, don’t worry, if you change the water regularly and clean the tank, molly fish fry can survive without a filter. Is it worth the risk, though? No, so better install a filter and a heater in a fry tank even before molly fish is ready to deliver the baby.


Summing up, Molly fish give live birth, and it can be a devastating experience for Molly owners if they do not know how to react. Molly fish are the hardiest freshwater aquarium fish, but pregnant Molly is weaker than you think, so make sure to take proper care of the molly fry and parent together. In addition, learning how to catch a Molly giving birth can ensure you can help them through this life stage. Finally, you need to keep foods like infusoria and brine shrimp ready for the baby molly fish in the tank.

If you want more information on Molly Fish Care, visit our website. We have all the articles that will help answer any questions about Molly Fish care.

Thank you for reading this post!

Good Luck!!

Happy Fishkeeping!!