How Long Do Mollies Live? Extend Their Lifespan!

Dec 19, 2021

How Long Do Mollies Live

Unfortunately, mollies don’t live as long as some aquarium fish do. And even though they’re hardy fish, they’re marred with generations of inbreeding and weak strains. So, how long do mollies live? Is it true that balloon mollies don’t live past 5 months? 

In this blog, I’ll shed some light on the lifespan of various molly variants. I’ll also give away a few tips you can apply to successfully extend your molly’s lifespan. 

Let’s start without further ado!

How Long Do Mollies Live? 

Like most livebearers, mollies live for anywhere between 2 to 5 years in captivity. With the right care and diet, you can stretch your fish’s lifespan up to 5 years. However, due to long transportation, inbreeding, and weak strains, most mollies seldom make it past their 3rd birthday. 

This is especially true for balloon mollies that are plagued with inherent health conditions as a result of selective artificial breeding. 

So, although mollies don’t take the title home for longest-living freshwater species, I must say that there is some wiggle room depending on what molly variant you have. 

Now, let’s look at the tentative lifespan of different molly types. 

How Long Do Dalmatian Mollies Live? 

On average, a dalmatian molly lives for anywhere between 3 to 5 years. However, there have been some reported cases where they’ve lived past their sixth birthday too! 

So, if you take good care and have a bit of luck, your molly can easily live for as long as 5 years. 

How Long Do Black Mollies Live? 

Credit: GFDL (Creative Commons license)

Black mollies don’t live as long as the dalmatian variant. However, with the right environment and diet, they have a lifespan of about 3 years in captivity

To emulate their natural habitat as closely as possible, add a bit of salt in their water. 

How Long Do Orange Mollies Live? 

Orange balloon mollies live for 2-3 years on average. This answer echoes with the experience shared by hobbyists on different forums. 

These fish are a result of years of inbreeding. Therefore, their health is pretty fragile. They’re vulnerable to several health conditions. 

How Long Do Lyretail Mollies Live?

Credit: Segrest Farms (Creative Commons license)

On average, lyretail mollies live for anywhere between 2-5 years. 

These are peaceful fish that thrive in hard, alkaline waters. If the water is acidic or soft, this might cut their life short. 

How Long Do Balloon Belly Mollies Live? 

Credit: Gourami Watcher (Creative Commons license)

Balloon belly molly fish generally live for 2-3 years. However, they are known to make it up to the 5th year with the right care. 

Balloon mollies are plagued with a genetic defect that causes their spine to develop irregularly. Therefore, they’re comparatively more susceptible to a number of health complications. 

How Long Do Sailfin Mollies Live?

Credit: Falashad (Creative Commons license)

A sailfin molly’s lifespan ranges between 3-5 years. 

Although freshwater fish, they can tolerate a wide variety of salt levels in a tank – even pure saltwater! 

How Long Do Gold Dust Mollies Live?

Like sailfin mollies, gold dust mollies too live for 3-5 years. 

If you get the water conditions and their diet right, they can even make it past their 5th birthday. 

These are peaceful fish that prefer hard water. They can be kept in both freshwater and saltwater tanks with step-by-step acclimatization. 

Now that I have answered the main query, let’s move on to a new section where I’ll share some ‘tricks’ you can pull to extend your molly’s lifespan. 

Disclaimer: There’s no secret formula or a hard and fast rule!

How To Extend Molly Fish’s Lifespan? 

There’s no magic potion or shortcut to increase molly fish’s lifespan. It all boils down to the kind of care you provide and the food you feed. Sometimes, even when you do everything right, the fish dies an untimely death owing to its weak genes. So, always make sure you get the fish from a trusted seller and provide it with a clean, stress-free environment. This will help ensure the fish lives the longest it can. 

Maintaining The Right Water Parameters 

Here’s what the ideal water parameters for mollies look like:

  • pH: 7.5-8.5
  • General Hardness: 15-30 dGH
  • Carbonate Hardness: 20-30 KH
  • Ammonia: 0 PPM
  • Nitrite: 0 PPM
  • Nitrate: Below 20 PPM

In the wild, mollies live in brackish water where the rivers join seas and oceans. Therefore, they can be easily transitioned from a freshwater tank to a saltwater tank. 

However, you must acclimatize them to saltwater gradually using the drip acclimation method. Like any other fish, they don’t react too well to sudden changes in their environment. 

Although mollies don’t grow gigantically as some other fish do, they produce a good amount daily bioload. 

Therefore, you must stay on top of the water quality to prevent the buildup of harmful toxins like ammonia and nitrite. Even the slightest exposure to these compounds can have irreversible effects on your molly fish. 

For example, if ammonia keeps on accumulating inside your molly’s body, the fish will become unable to extract energy from the food it consumes.

And before you know, the lethargy will transform into a coma, and your fish will die untimely. 

Here are a few signs of ammonia poisoning in fish:

  • Increased mucous secretion 
  • Red, bleeding gills 
  • Darkened body colors 
  • Increased respiratory rate 
  • Secondary infections 

Here are a few signs of nitrite poisoning in fish:

  • Brown gills 
  • Listlessness 
  • Rapid gill movement 
  • Gasping for air
  • Anemia (in severe cases) 
  • Limping near the water outlets 

Here are a few signs of nitrate poisoning in fish:

  • Lethargy 
  • High respiration rates 
  • Lack of appetite 
  • Laying at the bottom 
  • Curled head to tail (in severe cases)

There are several over-the-counter products available to eliminate the traces of these harmful compounds. 

I’ll add the links to ammonia, nitrite, and nitrate remover. 

However, it’s not wise to rely on these products all the time. You must zero in on the root cause and address it. 

If it’s overfeeding, cut back on the portions you give. If it’s frequently polluted water, amp up your filtration system and perform routine water changes. 

If you think there are not enough beneficial bacteria in the tank, add some. 

In a nutshell, here are a few things you can do to keep the water quality pristine for longer:

  • Perform routine water changes as needed 
  • Cycle the tank before adding fish
  • Improve filtration system 
  • Add beneficial bacteria 
  • Cut back on feeding 
  • Add live plants 
  • Increase aeration 
  • Vacuum the gravel 
  • Always remove uneaten food 

Keeping Stable Temperature 

The ideal temperature for molly fish falls within this range: 75-89 degrees Fahrenheit (24-24 degrees Celsius). 

Even though molly fish are quite hardy, they react negatively to sudden changes in temperature. As a matter of fact, sudden fluctuations in temperature are more deadly than being exposed to the wrong temperature for fish. 

For example, if the water is too hot, the tank’s oxygen levels will decline. If not rectified on time, your fish will slowly suffocate to death. 

If you find your fish constantly lying at the bottom of the tank, the likely culprit behind it could be hot water. 

Let me explain. 

Hot water, which has a lower oxygen concentration, moves to the surface. Relatively cooler water that’s more oxygenated will settle at the bottom. 

So, fish will prefer staying at the bottom to breathe in easily. 

Here are a few telltale signs of fish suffocating:

  • Loss of appetite 
  • Lethargy 
  • Panting 
  • Rapid gill movement 

And it’s not just hot water that’s dangerous. Cold water can be equally menacing, if not more. 

For starters, exposure to cold water will make the fish sluggish as its metabolism will take a backseat. 

Next, your molly’s immune system will be compromised – exposing the fish to several bacterial, fungal, and parasitic pathogens that are ever-present in the tank. 

Worst case scenario – consistent exposure to cold water has also been linked to popeye disease, characterized by abnormal protruding of the eyes. 

The location of your tank also dictates the temperature changes. Make sure it’s not placed in a spot that receives direct sunlight. 

Also, steer clear of spots directly under heating and cooling vents. 

Feeding The Right Diet 

Diet can make or break a deal when ensuring a molly’s longevity. 

Deciding what, when, and how often to feed your mollies can be tricky. Everyone has their own unique style they swear by. 

From what I researched, the general consensus is to give two meals a day. And provide them with an amount they can finish within 5 minutes. 

And mind you, mollies are voracious eaters. So, don’t get swayed and give them more than their body needs. 

This won’t just make them obese and deteriorate their health but also make the water dirty quicker, which once again comes with its own set of disadvantages. 

Like overfeeding, underfeeding can compromise your fish’s lifespan too. Like any other fish, the key nutrients mollies need in bulk are phosphorus and calcium. They also need trace amounts of sodium, magnesium, potassium, and zinc. 

Luckily, most commercially available food these days are specifically formulated to meet tailored nutritional requirements of fish like mollies. 

Therefore, you need to zero in on quality flake food or pellets. You can also get multiple and alternate between them. Mollies accept all kinds of food readily. 

For treats, you can give protein-enriched freeze-dried and frozen food like bloodworms, crickets, daphnia, and brine shrimp. 

Make sure that you don’t go overboard with treats. This could result in your fish deterring its staple food. 

Properly Cycling The Tank 

Unfortunately, an uncycled tank is the number one reason behind the untimely demise of our aquarium fish. Beginners are most likely to make this mistake. 

A tank takes several weeks to be fully cycled. There’s no shortcut here. Every aquarium on the planet has to go through this long, meticulous cycling process. 

It basically refers to the process of establishing bacterial colonies that regulate the tank’s nitrogen cycle – a method of conversion of ammonia to nitrite to nitrate. 

Your fish aren’t the only creatures that live inside your tank. There are entire colonies of good bacteria present that have a symbiotic relationship with the fish. 

The bacteria feed on the leftover fish food and the waste they produce. In return, they detoxify harmful compounds and make the tank hospitable for your fish. 

Good bacteria supplements like this one here from Aqueon can boost and ease the development and reproduction of these bacteria. 

Here’s a quick look at the steps involved in a tank’s proper cycling:

  • Begin by adding treated and dechlorinated tap water to your aquarium. 
  • Evenly add flake food to the water every day as if you’re feeding the fish. 
  • Monitor the level of ammonia 
  • Continue adding flakes 
  • Once the ammonia levels are high, start measuring the nitrite levels too 
  • Ammonia levels will decline as ammonia-eating bacteria flourish, but nitrite levels will spike 
  • Ammonia and nitrite levels will drop to 0 ppm, and nitrate will begin to appear as nitrite-eating bacteria too develop 
  • The nitrogen cycle is complete when ammonia and nitrite are at 0 ppm, and nitrate is below 20 ppm

Buying From A Credible Seller 

If the mollies you buy from one specific seller keep dying – not once, not twice, but always – we have a problem here. 

You need to switch to a new seller. Sadly, mollies are not often bred in the best conditions. They’re victims of excessive inbreeding, leading to the development of weaker strains marred with genetic defects. 

So, you must buy from a seller that you fully trust. Don’t give anyone the benefit of the doubt. 

Go to the pet shop yourself, watch how the fish are kept, and clearly observe the fish you will buy for any signs of injury or abnormality. 

Another thing to prioritize is buying your fish locally as much as possible. This will save the fish from unsolicited travel it has to make in a plastic pouch under rough conditions. 

Fish that have to go through a rough journey often die as soon as you place them in the tank. That’s because they’re stressed profusely.

Getting A Big Tank 

Mollies need a big tank. I cannot stress this fact enough. They’re often advertised to be suited for small tanks, but that’s far from the truth.

Mollies are active swimmers and should be kept in big numbers as they’re shoaling fish. They also produce a sizable bioload every day. Therefore, a small tank won’t just cut it for mollies. 

With small tanks, mistakes are magnified. For example, the same amount of leftover will yield a higher concentration of ammonia in a small tank than in a big tank. 

So, small tanks are more prone to getting polluted and toxic than big tanks. Also, even the slightest change in water parameters can disrupt the entire environment of the tank. 

A big tank also offers more room for exercise. And naturally, exercise is linked with good health and longevity. 

On the other hand, a small and overcrowded tank will stress out your mollies who need to swim a lot. It can also give rise to territorial animosity among different tank residents. 

This will naturally stress the fish. And as you already know, stress weakens a fish’s immunity and makes it prone to a host of secondary health conditions. 

Using The Right Equipment 

There’s nothing that gets on my nerves as seeing a fish in a vase, bowl, or tiny container without any filter or water movement does. 

Proper filtration, heating, and current are imperative to a fish’s wellbeing. You simply cannot get away without them. 

There are hundreds of styles to choose from. So, I am sure you will find filters and heaters that suit your taste. 

I have already explained above why maintaining the right water parameters and stable temperature are critical. So I won’t repeat myself again – you know the drill. 

Although aerator stones aren’t as indispensable as a heater or a filter, your mollies will highly benefit if your tank has one. 

Adding aerator stones are important for two main reasons: a) it enhances the tank’s oxygen levels, making it easier for your mollies to breathe b) Mollies love bubbles. 

Mollies, like most fish, simply love playing with the bubble streams that the aerator creates. It will keep them amused and occupied for hours. 

And without a shadow of a doubt, fish that can breathe easily and have a good time will live longer than those who don’t. 

Choosing The Right Tankmates 

Although I have added this point towards the end of the article, it’s super important that you carefully choose tankmates for your mollies. 

You might think two certain kinds of fish would amp up your tank’s aesthetics, but there’s a good chance that both of them will be unhappy and possibly dead if they don’t get along. 

Mollies are peaceful and friendly fish. That’s why it’s crucial to pair them with fish of similar temperament. Unfortunately, they most likely cannot hold their own against aggressive species like convicts and oscars. 

That being said, mollies too can get aggressive if the tank is too crowded or towards the breeding season. 

The best tankmates for mollies would be mollies. These are schooling fish that love to stick together. Therefore, you should at least keep 4 of them together. 

And here’s a list of other compatible fish that make good tankmates for mollies:

  • Bolivian Rams 
  • Keyhole Cichlids
  • Endlers 
  • Swordtails 
  • Gouramis 
  • Tetras 
  • Danios 
  • Platies 
  • Guppies
  • Corydoras 
  • Plecos 

Adding Live Plants 

In the wild, mollies exclusively live in densely planted areas and feed primarily on plants. Thus, they would very much appreciate it if their tank had some greenery. 

I can go on and on about why adding aquarium plants in a fish tank is a good idea. While they won’t directly lengthen your fish’s lifespan, they provide many benefits that go on to enhance your fish’s wellbeing and increase their lifespan in the long run. 

Besides providing a stunning natural look to your tank, they also significantly help reduce waste by using them as nutrients and releasing oxygen into the water. Plants help to take the load off chemical filtration. 

Some other benefits of aquatic plants include aeration of the water column, reduction of algae growth, and serve as a sanctuary for fish/fry.

Keeping Fish First Aid Kit Handy

It’s super important to keep a fish first aid kit handy for rainy days. Surely, knowing what to look for and use if the fish is ill to nurse it back to health is an excellent way to extend the fish’s life. 

Stock up on some essential medications like antifungal meds, ich meds, parasite meds, and kanaplex, as well as conditioners and test kits. It’s also wise to have battery-powered air pumps handy if the power goes out. 

And don’t forget to keep a hospital tank handy. You’re not supposed to fill it with water on an ad-hoc basis. It’s supposed to be already set up and cycled. 

Final Words: How Long Do Mollies Live?

Mollies don’t boast the longest lifespan. They can live for anywhere between 2-5 years. However, it’s not entirely impossible for them to live past their fifth birthday provided that you give the right care. 

Some variants, like balloon belly mollies, are susceptible to illness more than others due to their genetic buildup. As a result, their lives are often cut short. 

Nonetheless, emulating the natural environment as much as you can, feeding the right diet, and making the fish feel safe and happy goes a long way in extending their lifespan. 

Recommended Readings!

How Long Are Molly Fish Pregnant For? Twice As Long As Guppies!

What Do Molly Fish Eggs Look Like? Little Yellow Balls!

rohit gurung author at urbanfishkeeping

About Rohit Gurung

My never-ending love and fascination with Aquascaping started when I received a red-eared turtle for my 10th birthday.

Apart from researching and writing, I spend hours gazing at my 3 turtles. And yeah, I bask alongside them too.