Do Mollies Die After Giving Birth? How To Care For Mollies

Molly fish are becoming popular with aquarists these days. If you decide to add it to your aquarium, taking care of their problems, such as health issues, proper tank requirements, cause of death, and more, is essential.

A common question about these fish is, “Do mollies die after giving birth?” We’re going to shed some light on this topic now!

Do Mollies Die After Giving Birth?

There are many reasons why molly fish die after giving birth

Mollies can die after birth for various reasons, but it is not always. If you take care of pregnant molly fish properly, their chances of dying are extremely low.

Mollies are healthy fish. Females reach sexual maturity after half a year. On average, these fish spawn every twenty-eight days. They can produce hundreds of fry. But sometimes molly fish die after giving birth.

During pregnancy, mollies can be more sensitive to the elements than usual, leading to the common possibility of death after birth. So it is essential to understand the cause of death in these fish and how to prevent it.

What Causes Mollies to Die After Giving Birth?

Why do mollies die after giving birth?

Various factors can cause the death of mollies after giving birth. These include:

Lack Of Right Care During Pregnancy

Mollies can die after giving birth due to lacking proper care during pregnancy. They require much attention and the right food varieties to stay healthy. 

They can die if their environment isn’t clean, nutrition intake decreases, or toxins in the water.

Old Age

Molly fish can die after giving birth due to old age. Mollies usually have a lifespan of five years. At the end of their natural life cycle, their bodies can become very weak, and they may die after pregnancy.


Mollies can feel stress during pregnancy if their living environment changes drastically. Stress during pregnancy can make them more susceptible to fin rot, dropsy disease, and more.


Overbreeding can make mollies have more than a hundred babies, increasing the pressure on their bodies enormously. It also strains their immune system as they have to fight off diseases such as Dropsy disease.

Lack of Oxygen

Molly fish will require a lot of oxygen during pregnancy as their eggs develop inside their bodies. 

So if you don’t keep them in a well-oxygenated tank, they will die of suffocation. 

In addition, lack of oxygen can cause these fish to become lethargic, making them more susceptible to diseases such as Dropsy disease.


Mollies can die after giving birth because of malnutrition. Mollies feel lazy and weak, which is a common sign of malnutrition. It can make these fish more susceptible to fin rot, dropsy disease, internal infections, etc.

Malnutrition can occur if you overfeed your mollies. Overfeeding can cause their body toxins to increase, making them feel very lethargic and weak. It makes these fish challenging to protect their babies and more susceptible to diseases.

How to Keep Molly Fish From Dying After Giving Birth?

Some ways to keep molly fish from dying after giving birth.

Here are some ways to reduce the chances of this phenomenon occurring:

Prevent And Treat Disease

Some diseases can be treated by increasing the temperature. Also, others are eliminated by using aquarium salt. You can use one of the drugs and antibiotics on the market. In some cases, a water change can do the trick.

Many infections and illnesses can be traced back to a poorly maintained, dirty tank. Improving your tank’s conditions debilitates the strength of many diseases while empowering your mollies’ immune systems to fight back. All you need to do is remove leftovers and rotting organic matter like dead fish and plants.

Give your fish a balanced diet, including brine shrimp, bloodworms,  zucchini, and lettuce, not to mention pellets and flakes.

Mitigate Male Aggression

You can add several more female mollies to your aquarium. It will divert the attention of males. Also, we recommend adding more decorations and plants to give female mollies more hiding places. 

If the aggression of your male mollies has refused to abate, adding a divider to your tank is alright. It will keep males away from females.

Maintain Proper Water Conditions

Try maintaining one clean aquarium by changing the water regularly to remove toxins. Check the heater and the filter to ensure they operate optimally. Finally, check out the tank water frequently to ensure all the parameters are proper.

Before your molly fish mate, you must ensure they are housed within a sizable aquarium of at least ten gallons. 

In addition, avoid overcrowding. Small, overcrowded aquariums will cause stress that leads to death during/after giving birth.

Facilitate the Labor Process

We recommend facilitating the process by removing all distractions. It may include placing your tank in an area with no traffic.

In addition, you should stay away from your fish as much as possible during spawning. Your presence might delay the birthing process.


Do Mollies Eat Their Babies?

The answer is No. Molles don’t eat their babies. Instead, they’re very protective of their offspring. They just eat the babies and eggs of other smaller fish.

What Is The Most Common Cause of Death In Mollies?

The most common cause is a lack of oxygen in the tank water.

How long is the Lifespan of a Molly Fish?

In general, the lifespan of these fish is three to five years.

When Do Mollies Give Birth?

Mollies usually give birth when they are about two years old, although some start giving birth as young as six months old.

Why is My Molly Not Giving Birth?

  • Genetics.
  • Breeder Nets.
  • Bullying Tankmates.
  • Abrupt Changes.
  • Inappropriate Water Conditions.
  • And more.

Final Thoughts

Do mollies die after giving birth? Yes, there are many reasons why mollies die after giving birth. But you can do something to prevent this from happening.

If you have any queries regarding mollies, feel free to comment or check out our other posts. Thank you for your interest in the article!