How Fast Do Molly Fry Grow?

As an aquarist, you may wonder how fast it will take for your molly to grow. However, this article contains research that answers the question on how fast molly fish grow?

So, how fast do molly fry grow? Molly fry reaches adulthood when they are about four months of age. At this age, they are sexually matured and can be selected for breeding.

The growth rate of mollies fry sometimes varies due to some external factors. However, fish-keepers can enhance their growth rate by meeting some requirements.

How to Introduce Your Molly Fry into Your Home Aquarium?

You must understand the right steps in taking care of molly fish before introducing them to your home aquarium. Moreover, the severity of care you give your molly fish can determine how fast, and how well they grow.

Separating the mother

To ensure the survival of your molly fry, you should remove the mother from a community tank when she is close to giving birth. Also, adult mollies, especially males, tend to eat young mollies. Moreover, you will know the mother is close to giving birth, by observing if her abdomen is swollen, or the spot near her anal fin is darkened.

The time required to place the fry in its home

Whether you got your fry from a fish store or a breeder, ensure it doesn’t take long before you place it in its a new home. Also, if it’s your adult molly that gives birth, it should not take a long time before you place the fry in their new home.

Moreover, the means of carriage should be a large plastic fish bag with warm water in it. Ensure you are fast about placing them in the new home, as it helps minimize stress.

Acclimate the fry

Acclimating the fry is important before introducing them into the nursery tank. Also, this will help prevent shocking the fish, which may have led to their death. Moreover, acclimation is done by placing the bag holding the fish on the surface of the aquarium tank.

Also, allow the bag to float for at least 15 minutes. This helps regulate the bag water temperature to the temperature of the nursery tank. Finally, you let the fry out of the bag by allowing it to swim freely into the nursery tank.

How to Raise Your Molly Fish Fry?

Changing the water

You should have a filter in your aquarium tank. However, you should change the water regularly, to ensure the optimum health of your fry. Also, when you change the water in the nursery tank, you can acclimate them with water from the standard aquarium before introducing them back into the nursery tank. Moreover, ensure to replace 20 percent of the water in the tank every 3 days.

Fry growth

Ensure to monitor the growth rate of your fry. As this will help you to determine if they are growing well or not. However, you can introduce the fry into the standard aquarium when they are too large to fit into the adult’s mouth. Usually, this is within the period of 1-2 months after birth. Also, make sure you are not moving the fry prematurely, as it may cause tension between the fry and the adult fish.

Feeding Molly Fish for Breeding

You need to be more deliberate about mollies feeding during breeding. At this stage, you can either feed them frozen or live foods. Such as bloodworms, and brine shrimp. Regardless, ensure you feed them enough veggies at every stage they are at. Because, veggies fiber helps in improving their digestive system.

However, ensure you don’t overfeed them at once, as molly fish can be voracious, and they tend to eat almost everything you offer them. Moreover, by feeding them too much, they become overweight and heavy. This may cause them to wear out.

Factors That Influence the Lifespan of Molly Fish

Molly fish can live up to a reasonable number of years. However, their lifespan is majorly influenced by two or more of the following factors;


The quantity and quality of food you feed your mollies can determine their life span. As mollies are omnivores and they mostly feed on algae, plant matter, and small invertebrates.

However, to sustain their longevity, you should ensure to feed them a variety of diet. Such as vegetables, and high-quality flake food. Also, you can have a mix from their favorite veggies, which include, cucumbers, zucchini, shelled peas, and lots more.

Heaters and Filters

To increase the lifespan of your molly fish, you will need to add a suitable heater and filter to the aquarium tank. In most cases, the aquarium tank has beneficial bacteria, due to the filtration process of the filter. Also, the heater prevents the survivor from harmful bacteria. As these bacteria cannot withstand the normal temperature requirement.

Also, ensure to set the water temperature between 75-80 degrees Fahrenheit. Besides, maintaining cleanliness in a tank can also influence the health status of your molly fish.

Aquarium Size

The size of your home aquarium is a major factor you will want to consider. You must ensure that the aquarium is large enough to accommodate the amount of fish you are keeping inside. Whereby, the tank will be large enough to enable the molly fish to swim around freely.

However, you will need to get a 10-gallon size for small variety such as short-finned. Also, more than 30-gallon size for a large molly fish. However, the point is providing them with enough space as much as you can.

Related Questions

There are several questions that many aquarists have searched for, as regards molly fish. However, this article will help provide answers to some questions concerning the growth of molly fish

How Can I Extend the Lifespan of Dalmation Molly Fish?

Here are few tips that will guide you in extending dalmation molly lifespan.

  • You need to provide an appropriate filter for your molly fish tank. The availability of water is important as the molly fish excrete plenty of nitrites, nitrates, ammonia, and toxins from the body. Also, mollies leave food articles at the bottom of the tank, which may be detrimental to their health if they are not filtered out. So, ensure you get a filter that can remove waste, ammonia, and toxins.
  • Like a tropical fish, mollies need warm water to stay alive for a long time. Moreover, it is recommended that you add one tablespoon of aquarium salt to a gallon of tank water. This helps to extend the lifespan of molly fish because they tend to thrive best in freshwater conditions.
  • Another way to extend the lifespan of dalmation molly is by feeding them quality nutritious foods. These foods include pellets, brine shrimp, daphnia, insect larvae, and fish flakes. Moreover, these foods are known to be highly rich in minerals, vitamins, and proteins.
  • Lastly, make sure you change the aquarium water at least twice a week.

Can Mollies Live in Hot Water?

Molly fish are known to consume water rich in PH and salt. However, many fish exhibit this behavior. But, the facts remain that, molly fish will not consume warm water, if you place them in a temperature above eighty degree Fahrenheit.

Can Mollies Live in A Fish Bowl?

Yes, you can keep your molly fish in a bowl. But, ensure the bowl is big enough to allow them to freely move around. The size should be at least 10 gallons. However, it is most suitable if you are only using it as a temporary home.