Molly Fish Lifespan – How Long do Mollies Live For?

Regardless of skill level, knowing the lifespan of your fish is important, so you can be prepared to care for them for the entire duration of their lives and know what to do so they can live a long life.

In your research on molly fish, you’ve probably searched information on how long mollies live for and what can you do to improve molly fish lifespan.


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In this article, I’m going to answer these questions and other aspects related to the life expectancy of molly fish such as:

  • How long do male mollies live compared to female mollies?
  • Can you improve molly fish longevity?

With these aspects in mind, here’s what you should know about the lifespan of molly fish:

What is the Lifespan of Mollies?

When it comes to the lifespan of fish, a number of factors come into play — e.g. whether the fish is kept in captivity or lives in the wild, whether they have good genetics, whether they’re fed well or kept in proper conditions.

Most fish live longer in the wild than in captivity, even if you would be inclined to believe that since they get access to food so readily, they would live longer in captivity, but it’s the other way around. Fish usually live longer in the wild.

Unfortunately, aquariums are closed ecosystems, where water balance can be easily disturbed. Plus, an aquarium cannot compete with the natural habitat of fish.

That said, there are differences in life expectancy between the various molly fish breeds, however, on average, molly fish live 3-5 years.

Life expectancy can be maximized with proper care. Below, I discuss some of the ways you can prolong the lives of your molly fish.

How to Improve Molly Fish Longevity?

As I mentioned, there are various factors that are at play when it comes to the lifespan of molly fish (and all fish in general). These are:

  • Genetics
  • Food quality
  • Optimal water parameters
  • Optimal environment

Let’s analyze each of these in more detail.

1. Molly Genetics

It’s no secret that good genetics is one of the major building blocks of longevity in any living creature. If your fish have bad genetics, everything else comes second to it.

Therefore, seek out reliable and trustworthy breeders when purchasing your starter molly fish. A good breeder will focus on breeding healthy fish with good genetics. Often, fish with a bad genetic profile don’t even live long enough to become adults.

Some pet stores can also be a good place to source your fish from, but breeders are a superior choice when it comes to knowledgeability about good fish genetics.

Another argument in favor of getting your fish from a breeder is that aquarists often report lower lifespans in fish sourced from pet stores compared to fish purchased directly from a breeder.

2. Feeding Mollies Quality Foods

Another way you can improve molly fish longevity is to feed your mollies a diet that closely resembles the one they have access to in the wild.

Molly fish are omnivorous and accept a variety of food types. Vegetable matter is quite important for them as they also feed on algae in the wild.

Thus, it’s important to feed them quality foods and offer them a diverse diet that can contain commercial foods and foods that you prepare at home.

When opting for commercially available foods, choose a quality brand and offer your mollies flakes, freeze-dried brine shrimp, frozen bloodworms, tubifex, spirulina tablets and veggie tablets.

Homemade fish food is also a great option for feeding your molly fish. Offer them soft-boiled vegetables like cucumbers, green beans, carrots, spinach, etc.

If you don’t mind cultivating fish food at home, you can opt for live food cultivation like brine shrimp, vinegar eels, daphnia for a protein-rich diet.

Regardless of the type of food you offer them, be very careful not to overfeed your mollies. Offer them food once or twice a day and limit the food to an amount they can eat in 3-5 minutes.

3. Ensuring Optimal Water Parameters for your Molly Fish

Another crucial element in prolonging the life expectancy of your fish is determined by the water parameters in the aquarium.

Strive to ensure stable tank conditions and in parameters that are suitable for your mollies. The water requirements for mollies are as follows:

  • Temperature: 70 °F to 82 °F
  • Water pH: 7.0-8.0
  • Water hardness: 15-30 dGH

These are the general guidelines for molly fish but be sure to check the specific requirements for the molly breed you choose for your aquarium.

Perform regular water changes, keep the tank clean and treat the water use for water changes. You can use water conditioners like the Seachem Prime to eliminate chlorine and heavy metals.

4. Ensuring a Stress-Free Environment for your Molly Fish

Providing a stress-free environment means eliminating anything that can be a source of stress for your fish:

  • Incompatible tank mates;
  • Overstocked tank;
  • Inadequate male to female ratio;
  • Lack of hiding spaces;
  • Too much light, etc.

Choose compatible tank mates for your mollies (guppies, platies, bristlenose plecos, harlequin rasboras, etc.), be careful not to keep too many fish in your tank and offer plants and decorations for hiding.

Keep a lighting schedule and make sure you observe correct female to male ratio in the tank.

Live-bearers like mollies breed a lot and male mollies tend to pursue females constantly, thus, stressing them out. Keep one male to 3 females to avoid stressful conditions for females.

Female or Male Molly Fish – Which Live Longer?

There isn’t any evidence that males molly fish live longer or less than female molly fish, however, a female molly fish that spawn constantly will have a shorter lifespan. The same is true for male mollies that mate with females all the time.


If you want to raise and breed healthy molly fish, following the tips I discussed in this article will go a long way in expanding the lives of your fish.

Fish that have good genetics, are fed a varied and qualitatively superior diet, and are kept in excellent water and tank conditions will go on living a long and healthy life.

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