How Many Babies Do Mollies Have? - "My Silver Molly had babies" by 3n is licensed under CC BY-ND 2.0.
How Many Babies Do Mollies Have? - "My Silver Molly had babies" by 3n is licensed under CC BY-ND 2.0.


Diving into the fascinating world of freshwater aquariums, enthusiasts are often captivated by the vibrant colors and intriguing behaviors of various fish species. Among these captivating aquatic creatures, mollies (Poecilia spp.) stand out as one of the most popular and cherished choices for aquarium keepers. These small, lively fish are not only admired for their stunning appearance but also for their unique reproductive strategy. As live-bearers, mollies defy the traditional method of egg-laying and instead give birth to live, fully-formed fry, which begs the question, “How many babies do mollies have?” In this article, we will delve into the captivating lives of mollies, exploring their appearance, behavior, and the wonder of their live-bearing nature, unlocking the secrets behind their popularity and the joy they bring to countless aquarium enthusiasts worldwide.

About Mollies

Mollies (Poecilia spp.) are popular freshwater fish known for their colorful appearance and interesting behavior. As live-bearing fish, they give birth to live, fully-formed fry, which is one of their distinctive features.


Mollies come in various colors and patterns, and their appearance can differ significantly depending on the species and specific strain. However, some general characteristics include:

  • Color: Mollies are often found in vibrant colors like black, silver, orange, yellow, and even combinations of these colors. There are also various pattern variations, such as marbled, dalmatian, and lyretail.
  • Body shape: They have a streamlined body shape, typical of most fish, with a dorsal fin on the top and an anal fin on the bottom.
  • Fins: Their fins can be quite elaborate, especially in certain varieties, like the sailfin molly, which has a large, sail-like dorsal fin.
  • Size: The average size of mollies can range from around 2 to 4 inches (5 to 10 centimeters).


Mollies are active and social fish with interesting behaviors that can vary between individuals and species. Here are some common behavioral traits:

  • Live-bearing: One of the most fascinating aspects of mollies is that they are live-bearers, meaning the females give birth to live, free-swimming fry instead of laying eggs. This is quite unusual among fish and contributes to their popularity among aquarium enthusiasts.
  • Schooling: Mollies are social creatures and tend to thrive when kept in groups. They often form schools and enjoy swimming together, which also adds to the aesthetic appeal of a well-stocked aquarium.
  • Peaceful nature: In general, mollies are peaceful fish, but like all fish, they can show territorial behavior, especially during breeding or when the tank is overcrowded. Providing enough space and hiding spots can help reduce potential aggression.
  • Active swimmers: These fish are known for their active nature, and they enjoy exploring their environment, so a well-decorated aquarium with plenty of swimming space is ideal.
  • Omnivorous diet: Mollies are omnivores, meaning they eat both plant matter and small aquatic organisms. In the wild, they feed on algae, small insects, and plant matter. In captivity, they readily accept commercial fish flakes, pellets, and even some live or frozen foods like brine shrimp and daphnia.

Overall, mollies are attractive and engaging fish to keep in aquariums, and their live-bearing reproduction adds an extra level of interest for fishkeepers. Providing them with a suitable environment, proper care, and compatible tankmates can lead to a rewarding and enjoyable aquarium experience.

How Many Babies Do Mollies Have?

So, how many babies do mollies have? The number of babies, or fry, that mollies can have in each brood varies depending on the species and the size of the female. On average, a molly can give birth to anywhere from 20 to 100 fry in a single brood. However, some particularly large or well-fed females may produce even more fry.

It’s worth noting that mollies are prolific breeders, and if they are kept in a suitable environment with proper care, they can reproduce quite rapidly. As a result, it’s essential to be prepared for potential population growth if you have mollies in your aquarium. Providing plenty of hiding spots for the fry and maintaining good water conditions will help ensure their survival and prevent overpopulation in the tank.

How Many Babies Do Mollies Have? - "My Silver Molly had babies" by 3n is licensed under CC BY-ND 2.0.
How Many Babies Do Mollies Have? – “My Silver Molly had babies” by 3n is licensed under CC BY-ND 2.0.

Caring for the Fry

Taking care of molly fry (baby mollies) is essential to ensure their survival and healthy growth. Here are some tips on how to care for them:

  • Separation: When the female molly gives birth, you may consider seperating the fry from the adult fish as they may eat the tiny fry. You can use a breeding trap, a separate nursery tank, or add floating plants that offer protection for the fry.
  • Proper tank setup: Use a small aquarium or breeding tank for the fry, as they require space appropriate to their size. The tank should have a gentle filter or a sponge filter to maintain water quality without creating strong currents that could harm the fry.
  • Water movement: Mollies are used to gentle currents in their natural habitats, so ensure that the filtration system or any air pumps do not create strong currents that could stress or harm the fry.
  • Water conditions: Keep the water clean and stable. Perform regular water changes to maintain good water quality. Test the water parameters regularly to ensure they are within suitable ranges for molly fry (temperature around 75-82°F or 24-28°C,).
  • Feeding: Provide appropriate food for the fry. Newly hatched fry can be fed infusoria or commercially available liquid fry food for the first few days. As they grow, you can transition to baby brine shrimp, powdered fry food, or crushed flakes. Feed small amounts several times a day, as their stomachs are tiny, and they need frequent feeding.
  • Hiding places: Offer plenty of hiding spots in the form of plants, fine-leaved structures, or commercial fry shelters. This helps to reduce stress and prevents the fry from being bullied or eaten by adult fish.
  • Monitoring: Observe the fry regularly to ensure that they are active, growing, and healthy. Remove any sick or dead fry promptly to prevent the spread of disease.
  • Gradual acclimatization: If you plan to move the fry to a larger aquarium with adult fish once they grow, make sure to acclimate them gradually to avoid any sudden changes in water parameters.

Remember, molly fry grow quickly, so be prepared for their changing needs as they develop. Providing proper care and a suitable environment will increase their chances of survival and lead to healthy, vibrant adult mollies.

Summing It Up

In conclusion, the world of mollies offers a captivating journey for aquarium enthusiasts, combining striking colors, lively behavior, and the wonder of live-bearing reproduction. These charming fish have earned a special place in the hearts of fishkeepers due to their easy-going nature and adaptability to various tank setups. As we’ve discovered, their appearance can vary greatly, with a wide range of colors and fin variations, adding a delightful visual appeal to any aquarium. Moreover, their peaceful and social behaviors make them a joy to observe.

However, the true marvel lies in their unique reproductive strategy. The question, “How many babies do mollies have?”, becomes an intriguing topic of discussion as we learn that each female molly can give birth to anywhere from 20 to 100 fry in a single brood. This live-bearing nature sets them apart from many other fish species, providing an educational and rewarding experience for aquarium enthusiasts, especially those interested in breeding.

As we care for and nurture these live-bearing gems, it’s essential to provide a suitable environment with proper hiding spots and adequate nutrition for their fry. By following responsible aquarium practices and ensuring the well-being of both adult mollies and their offspring, we can appreciate the full wonder of their life cycle and contribute to the conservation of these beautiful fish.

In essence, mollies exemplify the marvels of nature, showcasing the diversity and complexity of aquatic life. As we continue to explore and protect these enchanting creatures, we foster a deeper connection to the natural world and a sense of responsibility in preserving the delicate balance of our aquatic ecosystems. So, whether you’re a seasoned aquarist or a beginner with an insatiable curiosity, the journey with mollies promises to be an enriching and rewarding one, leading to countless hours of wonder and admiration for these exquisite live-bearing fish.