What to feed baby mollies

How to Care for Freshwater Baby Molly Fish

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Updated April 24, 2017

By Sonia Fernandez

The molly (Poecilia sphenops) is a popular fish for the beginning aquarist. They're attractive and hardy and, given enough space, can get along with others. Mollies belong to a class of fish called livebearers. They don't lay eggs; their young come out swimming. And they are prolific breeders as well.

Molly babies get no protection from their parents. The tiny fish are just as likely to be eaten by their own mother as they are by other fish in the aquarium, so to survive they're going to need a little help.

    Gather the babies. The best-case scenario would be to have the pregnant female in a breeding box or net suspended in the water of the aquarium. In the case of a breeding box, the babies would drop into another compartment of the box and the mother would already be separated. In the case of a breeding net, you would have to scoop the mother out. If you can't get to the gravid female in time, you may need to capture the little ones and separate them from the other fish in the aquarium. Then you can use the breeding box, net or the separate tank to isolate the fry until they get large enough to fend for themselves.

    If chasing tiny mollies around the aquarium doesn't do it for you (it also stresses them out), or if you just want to give the babies a little more protection, add real or artificial plants to the tank. Plants with leaves that float to the top of the tank will give the little ones a place to hide as they feed. Breeding grass also works for this purpose.

    Feed your fish. Baby mollies can eat your regular fish flakes, crushed finely. Live baby brine shrimp are also a popular baby food. Do not overfeed them. In about eight weeks your baby mollies should be large enough to go into the tank with the other fish.

    Things You'll Need
    • Fish breeding box or net
    • Separate tank, filled with water (optional)
    • Fish net, or other means of scooping out fish
    • Plants
    • Fish food
    • Preparation is the best insurance toward successfully caring for your molly fry. Plants should be in place, the pregnant females already separated. It saves you the time and effort of trying to separate the fish after they have been born.

      Mollies are prolific breeders, so to control the population it's recommended that the sexes are kept separate. Males have a gonopodium, a modified anal fin used for reproduction. You can determine a young fish's gender after about 12 weeks.

      Keep the babies' habitat clean. The breeder box or tank will need to be cleaned and its water changed. In a breeding net, the fry are exposed to the same water conditions the rest of the tank is experiencing.

      Cannibalism is normal with mollies and other livebearers like guppies and platys. As fecund as they are, you don't really need to worry about saving every last one.

Related Articles


  • FishLore.com: Livebearer Fish Species
  • wetwebmedia.com: The Truth About Mollies


  • Preparation is the best insurance toward successfully caring for your molly fry. Plants should be in place, the pregnant females already separated. It saves you the time and effort of trying to separate the fish after they have been born.
  • Mollies are prolific breeders, so to control the population it's recommended that the sexes are kept separate. Males have a gonopodium, a modified anal fin used for reproduction. You can determine a young fish's gender after about 12 weeks.
  • Keep the babies' habitat clean. The breeder box or tank will need to be cleaned and its water changed. In a breeding net, the fry are exposed to the same water conditions the rest of the tank is experiencing.
  • Cannibalism is normal with mollies and other livebearers like guppies and platys. As fecund as they are, you don't really need to worry about saving every last one.

About the Author

Sonia Fernandez is a writer living in Santa Barbara, California. Her background is primarily in news, as a general assignment reporter for a local news website, but she also does the occasional magazine feature, Web article, short story or travel piece. She holds a Bachelor of Arts in English from the University of California, Santa Barbara.

Photo Credits

Jupiterimages/Photos.com/Getty Images

Molly Fish Fry Care - How to Care for Baby Mollies?

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Molly fish breed easily and frequently, but they aren’t fish that will continue caring for their fry after they’re born. In fact, adult mollies most often end up abandoning or even eating their fry.

If you want baby mollies to survive, you’ll need to care for them yourself by separating them from adult fish and feeding them foods suitable for small fry.

In this guide, I will teach you how to care for baby mollies including how to save them from adult fish, how to feed them and how to maintain a molly fry tank.

How Mollies Are Born?

As live-breeders, mollies spawn completely formed fry that skip the egg stage and are ready to swim and feed in just a couple of hours.

Molly males become reproductive at 12 months, while females reach reproductive age at 6 months. Female mollies carry the eggs for about 30-45 days.

There aren’t any special requirements for breeding, it’s enough to simply keep male and female mollies in the same aquarium and breeding will occur without any further intervention.

The female molly will have an enlarged abdomen and will start looking for shelter in a darker corner of the aquarium as she’s preparing to give birth to the fry.

Spawning usually takes place in the early hours of the morning and the fry of some molly breeds are rather large (e.g. black molly fry).

The fry will hide in the leaves of the aquarium plants and they’ll stay low for a couple of hours until they’re ready to feed and swim.

How to Save Molly Fry?

If your molly fish produced fry in a community aquarium, don’t expect the fry to survive. Adult mollies and other fish will certainly mistake them for a tasty snack.

If you want to avoid spawning to occur in a community tank, avoid keeping both male and female molly fish in the same aquarium.

However, in cases of misidentified gender, it may happen that even against your wishes, female and male molly fish may end up in a community aquarium and breed.

Below, I’ll discuss some of the ways you can salvage the fry when they’re born into a community aquarium.

Ideally, you should have a separate breeding tank for the female molly fish and the breeding tank should match the parameters of the origin tank.

After the female molly fish has dropped the fry, you should remove her, so you can continue caring for the fry yourself and prevent the female molly from eating the fry.

Now, even if you don’t have a separate breeding tank, there are ways to save at least some molly fry:

  1. Use a large plastic container or glass jar to extract the female as she’s about the give birth and keep her separated from the other adult fish in your tank. Once she has dropped the fry, you can remove her and continue caring for the fry.
  1. A second method to separate the female molly fish and the fry is to install a breeding box into the main tank, which is a plastic mesh or container that’s designed to allow water to flow through, without allowing other fish into the mesh.

This method is the easiest if you don’t want to worry about matching the water parameters of the main tank as you would have to do with other methods of separating the fry from the adults.

  1. The third option is less desirable and its success rate in saving the fry isn’t as high, but it can help if you’re caught off guard. Adding plants to the tank such as java moss, hornworts, guppy grass or roots of water lettuce can provide hiding spaces for the fry for a few weeks until they grow large enough to not be mistaken for food by the other fish.

The next step in caring for the fry will depend on which method you’ve chosen from the above. If you’ve chosen to use a glass jar or plastic container, depending on its size, you may need to transfer the fry in a nursing aquarium, where you can offer them the proper conditions for growing.

Likewise, you can’t keep them in the breeding box for too long either.

How Long Can You Keep Molly Fry in a Breeding Box?

Molly Fry in Breeding Box

Setting up a breeding box is probably the easiest way to save molly babies from being eaten by adult fish.

However, you shouldn’t keep them more than 2 weeks in the breeding box, because this will significantly stunt their growth, which is undesirable regardless of whether you’re raising mollies for commercial purposes or as a hobby.

Larger mollies can release as many as a hundred fry at once, therefore, it’s easy to understand how so many fry can quickly outgrow their breeding box.

At about 2 weeks, molly juveniles are large enough to not be mistaken for food anymore and you can release them into the main tank or you can set up their own aquarium.

Feeding Molly Fish Fry

For fast growth, molly fish fry need a diversified diet and require frequent feedings with small amounts of food. These fish are constantly hungry because of their fast digestion cycle.

Since molly babies are so small, their mouth opening is also very small, therefore, you’ll need to procure size-appropriate foods that will fit their mouths.

The digestion cycle of molly fry is short, therefore, they’ll be ready to eat as soon as every half hour. You shouldn’t feed them that often, of course, but you should aim for at least 5 feedings a day.

As with any fish or fry, overfeeding can be a problem. Also, scoop out any uneaten food so as not to foul the aquarium.

If you’re keeping molly juveniles in the same tank with the adults, you can feed them whatever you’re feeding the adults, just remember to crush the flake foods or larger foods, so it will fit their mouths.

There are flakes like First Bites designed for feeding small fry, so you can opt for those instead, especially that they’re rich in protein to sustain rapid growth.

Live foods are another excellent food choice for small molly fry, and you can opt for baby brine shrimp, vinegar eels, daphnia, micro worms. If live food is not available, frozen or freeze-dried can be a good alternative.

Another protein-rich food source that I like to use when feeding small fry is hard-boiled egg yolk made into a paste. It’s easy to prepare, readily available in your fridge, and not to mention very cheap. I add small amounts of the paste once or twice a day.

A varied diet will strengthen the fry and will stimulate their growth.

Molly Fry Tank Maintenance

If you haven’t set up a separate tank for your mollies and you continue to keep them in the same aquarium with the other fish, tank parameters should be kept stable and water changes should be regular as molly fry are more sensitive to high toxin levels.

If you decide to set up a nursery tank for the fry, here’s what you should aim for:


Tank Size & Filtration

Depending on the number of molly babies, set up a tank between 10 and 20 gallons. Add a fry-safe filter system to keep the water clean in addition to performing regular water changes.

Add some plants to the tank too such as java ferns and grasses.

2. Temperature

Aim for a temperature a little above the temperature in the main tank (80 °F maximum). Warmer water speeds up metabolism and encourages the fry to eat more. In turn, this will help them grow faster.

To keep the aquarium heated at the optimal water temperature, you’ll require a heater to ensure consistent temperature.

3. Water Changes

To keep toxin levels low and refresh the water, aim for frequent partial water changes. I recommend 50% water changes twice a week. This will also facilitate the growth of your fry.

Water changes, of course, also depend on the number of fry you have and the size of your tank. Depending on how you stock your tank, you may get away with fewer water changes or you may need to perform more frequent water changes.

4. Lighting

Offer your fry 12-16 hours of light each day and 6-8 hours of darkness for rest. Good light conditions will ensure the healthy development of your fish.


Now that you know more about breeding mollies and caring for baby mollies, you can look forward to breeding your molly fish.

As you can see, raising molly fish fry isn’t particularly difficult, but you do need to take some precautions to save the fry and to maintain optimal tank conditions.

Unlike adult molly fish that are hardier, the fry is more sensible to high toxin levels or sudden changes in water temperature.

I encourage you to familiarize yourself with their requirements before attempting to breed molly fish. Feed them a varied diet, keep their water clean and tidy, and you’ll be rewarded with healthy and active fish.

Molly Fish

care, maintenance, reproduction, compatibility, food, photo review


Aquarium for mollies

For keeping medium-sized mollies you will need an aquarium of at least 50 liters, for large sailfish - at least 100 liters. It is better if the aquarium is extended, because mollies love to actively swim. The lid must be mandatory, the fish can easily jump out of the aquarium. Mollies are usually kept in small groups, where there should be 2-3 females per male. Fish swim mainly in the middle layers of the aquarium.

Mollies kept in groups dominated by females

Better all fish look in aquariums, decorated in a natural style. Wherein natural driftwood, stones, live plants are used. useful to do several hiding places in which females ready to spawn can hide, or weaker males.

Mollies love clean water, so a suitable internal or external filter should be installed in the aquarium. You will also need a compressor for aeration, especially at night, when plants do not emit oxygen.

Parameters water

Family pecilia is famous for the endurance of its representatives. And mollies are no exception. Fish easily adapt to a wide range of water parameters. Mollies prefer warm water with a temperature of 23-28 ° C. It must be neutral or slightly alkaline (pH=7.0-8.0). What When it comes to hardness, the fish do not like soft water, it is better if the GH value varies from 10 to 20.

In nature, mollies often live near the mouths of rivers flowing into the ocean. In such places, a mixture of fresh and salt water occurs. Therefore, the fish tolerate a gradual increase in salinity to a concentration of 2-3 g/l.

Mollies easily adapt to different water parameters

For to maintain water quality, it is necessary to change up to 20% of the volume weekly aquarium. Most often, when replacing, tap water is used, which can be dangerous for aquatic organisms, because it may contain traces of chlorine (and its derivatives), as well as heavy metals. Instantly secure water air conditioner Tetra AquaSafe. Just add 5 ml for every 10 liters of fresh water before how to pour it into the aquarium.


Mollies love bright light. Light day in the presence of living plants should be about 8 hours.


There are no special requirements for the substrate of mollies. It is best to opt for sand or small pebbles (3-6 mm), which are well suited for growing live plants. The layer thickness should be 4-6 cm. For long-term plant nutrition under neutral soil, do not forget to add a special substrate for plants - Tetra CompleteSubstrate.


In an aquarium with mollies, it is necessary to create areas with both islands of vegetation and open spaces for swimming. All popular types of plants are suitable for planting in an aquarium: cryptocorynes, echinodorus, cabomba, hygrophiles, etc. It should be noted that fish can bite the delicate leaves of some plants. To minimize the risk of this, fish should be fed with food with plant components.

Mollies among living plants

Feeding mollies

The omnivorous nature of mollies necessitates the inclusion of animal and vegetable products in the diet. Fish are not picky about food. However, long-term feeding only with high-protein foods (a variety of live and frozen foods) will sooner or later lead to disruption of digestion.

Optimal mollies food:

  1. TetraPro Algae is an innovative food, produced in a gentle low-temperature technology. Due to this process, even more beneficial nutrients. Contains prebiotics for comfortable digestion and spirulina algae concentrate to meet the needs of mollies in vegetable food.
  2. Tetra Phyll - complete food with herbal ingredients for daily feeding of ornamental fish. Supports resistance body and gives additional vitality. As part of the feed, the BioActive formula is a complex of selected vitamins for fish health and longevity. Available in the form of flakes and granules.
  3. TetraMin Flakes is a universal food for all kinds of aquariums. fish. It is made from more than 40 types of selected raw materials. Fully balanced, contains vitamins and microelements necessary for health, and also prebiotics for comfortable digestion. Light flakes for a long time float on the surface, which is convenient for mollies who prefer to eat near water surface.

Mollies, like many of their relatives in the family, have a calm and peaceful nature. The only exception is velifirs, which, due to their size and increased activity, can attack small neighbors.

Mollies get along well with their relatives guppies

Good neighbors for mollies will be peaceful proportionate fish, such as swordtails, platies, rasboras, danios, tetras, barbs, scalars.

Possibly keeping several breeds that differ in color, but only if you do not want to keep a pure line of one breed. Indeed, as a result of crossing fish with unpredictable colors can turn out.

Settlement of mollies with aggressive and large cichlids is not worth it. Even large species will be destroyed by predators in a short time.

Duration life expectancy

The life expectancy of mollies in home aquaria is 3-5 years.

photos, maintenance and care, compatibility

Molliesia (lat. Mollienesia) is an aquarium fish that I know even those who are far from a hobby. But not everyone knows that there are actually many different types of them: black, snowflake, velifera, sphenops, latipina However, whichever of these species you name, they are all popular and common in the aquarium and belong to the same species, although they sometimes look very different differently. And all because they have many advantages - they are peaceful, very hardy and unpretentious, inexpensive, and simply multiply. These are purely American fish, as they live in North and South America. Wild species can be divided into two groups - with short fins, such as black mollies and with long fins, such as velifera or marbled. 9Ol000 nature

This is a freshwater fish of the genus Poecilia, part of the family Poeciliidae. These fish are native to the Americas, but their habitats can vary greatly. It mainly inhabits the coastal regions of North and South America, but is also found in places where rivers flow into the ocean, in brackish water.

The whole continent can be called their homeland, they are so widespread.

  1. Black mollies or Sphenops (Poecilia sphenops) lives from Mexico to the northern states of the USA.
  2. Latipin Mollie (Poecilia latipinna) lives along the southeast coast of the United States and in Mexico.
  3. Velifera (Poecilia velifera) or high-finned (sailing) mollies native to the coastal regions of Yucatan and Mexico.

All of them are characterized by a wide range, unpretentiousness and omnivory, which makes them very common in these areas.

Most species appeared in aquariums as early as 1899, and various hybrids from 1920.

Now you can find black mollies, snowflakes (completely white or yellow), silvery, spotted. And the number of diverse species continues to grow and gain popularity.


Black mollies is one of the artificially bred species in 1930, it reaches a size of 6-10 cm in the aquarium, and up to 12 cm in nature.

Life expectancy is about 3 years, but may be longer.

Black has a completely black body, deep velvety shade. Often there are forms with a tail fin in the form of a lyre, a black lyre.

Latipina grows up to 10 cm in the aquarium, and up to 20 cm in nature. The body color is silvery brown, with dark and blue dots. A distinctive feature is the high dorsal fin.

Velifera as a whole is very similar to latipina, but now it has received a new and popular look - a completely white look has been bred from it - snowball.

Difficulty in content

Simple and unpretentious fish that are well suited for keeping beginner aquarists. This is especially true of the popular and common black molly.

Be careful only with disc forms, or as they are also called - balloon, because of their curved shape, their life expectancy is less than that of normal fish. The fact is that the shape of the balloon is scoliosis, with all the ensuing consequences.

For beginner aquarists, regular black aquarium mollies are the best choice as they are less demanding, easier to breed and require smaller aquariums.

Keeping all types requires a well-planted and spacious aquarium. It is important that their diet contains a lot of plant matter and algae.


What to feed mollies? Omnivorous fish that eat all types of live, frozen or artificial food.

But, they need a very large amount of fiber foods, such as algae or vegetables. The fact is that in nature, fish have a lot of algae and various fouling in their diet, this is evidenced by their lips and behavior. You can often see how they scrape the fouling from the glass and decor in the aquarium. They use their lips to scrape them off the surface.

The easiest way to feed herbal food is flakes with spirulina, or pieces of slightly boiled cucumbers, zucchini, lettuce.

From animals - bloodworm, tubifex, brine shrimp. In general, there are no problems with feeding, the main thing to remember is that plant foods are very important for them.

Artificial foods such as flakes and pellets are a good option. Try supplementing them with other foods to provide a wide range of nutrients.

Live and frozen foods are excellent sources of protein. Bloodworms and brine shrimp will happily be eaten, but most other options work well too.

Feed them small meals twice a day. This gives their digestive system the ability to process food. Give them as much as they can eat in two to three minutes.

Aquarium keeping and care

In the wild, the habitat of mollies can vary greatly. They have adapted to many different environments, including a tolerance for brackish waters and high levels of acidity.

For several fish you need about 60 liters, preferably from 100, because you will keep not only them. They themselves can grow up to 10 cm, and in very small aquariums they will be cramped.

Each additional fish will need about 5 liters to live comfortably. The main reason we preach that larger tanks are better is because they are easier to maintain. Fish can adapt quite easily to a smaller living space, but water quality is a factor that is highly variable in small tanks.

The more water, the easier it is to keep the aquarium clean. The larger your water container, the more diluted the water will be with fish poop and uneaten food that sinks to the bottom of your tank. The smaller the body of water, the easier it gets polluted.

Water parameters can be very different, as they perfectly adapt to local conditions. But it is recommended: water temperature 23-28C, ph: 7.0-8.0, hardness 20-30 dGH. Mollies bred in captivity are used to different environments, so you don't have to worry about each species needing different water.

Note that the fish tolerate salted water very well, and many resources even advise specially salting it.

Yes, it won't make them worse, but don't forget that by themselves they rarely live in an aquarium, but neighbors can tolerate increased salinity very, very badly.

I would recommend using salt only if they live in an aquarium alone or for quarantine purposes.

When it comes to decorating your aquarium, it's entirely up to you. It is recommended that it has a lot of plants, as mollies love to scrape off plaque and algae from them.

A layer of sandy substrate is a good idea. Although they won't spend much time on the bottom, the fine grains of sand are good for plant roots.

You can choose your favorite plants, but taller bushes like wallisneria provide good hiding places for these fish.

It is also desirable that there be a filter, and an internal one is enough. Be sure to change weekly up to 20% of the water, as they quickly pollute it.

Caring for them like all other fish: feeding and regular water changes, otherwise they are very undemanding.


First of all, these are completely harmless and peaceful fish. Great for community aquariums, compatible with any peaceful and small fish.

They are peaceful most of the time, but may show signs of aggression when the tank is full or they are surrounded by aggressive neighbors. Therefore, it is important that the aquarium is large enough and that they have suitable neighbors (more on this below).

Do not keep them with predatory and aggressive species. Other viviparous fish will be ideal neighbors: guppies, platies, swordtails. They are also compatible with many dissimilar species: gourami, angelfish, neon, barbs.

Mollies are active and sociable, so they enjoy swimming together. The pack should be predominantly female, as males are known to harass females.

Sex differences

It is quite easy to tell a female from a male. Females are usually larger, with a large and rounded belly. The most accurate difference is the shape of the anal fin, in males it is folded into a tube (gonopodium), and in females it is triangular in shape.


They breed like guppies, viviparous. That is, the fry eats is born already fully formed and capable of life, bypassing the stage of eggs.

A pregnant female bears fry for 30-40 days, the easiest way is to notice the time from the last birth, and report a new term.

Since it is possible to understand whether a female is pregnant only by the degree of rounding of her abdomen. With a high degree of probability, she will give birth to fry again.

No special conditions are needed for breeding, it is enough to keep females and males together in a common aquarium.

It is quite difficult to understand when a female has become pregnant, especially in blacks. The simplest thing is to watch her belly, she noticeably gains weight when she has fry.

The female gives birth about every 40-45 days, so you can just mark the day of the last birth and wait. So that the fry are not eaten, it is better to put the female in a separate aquarium, always with plants.

The fry that are born are usually large and begin to feed immediately.

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