Can Guppy Live With Molly? (Precautions To Take?)

Guppies and mollies are peaceful fish species and do great in a community tank. But, Can guppy live with molly? Will it create any issues?. Let us find out.

Guppy can live with molly as they are peaceful fish and require similar water parameters and dietary needs. However, mollies can be aggressive if we keep them in an overcrowded tank and will nip on guppies fins when being aggressive. Therefore, provide ample space for both fish to live comfortably.

This article will discuss the precautions to take when adding mollies to our guppies aquarium. Also will discuss how to take care of guppy and molly fry. So let us get into it.

Can guppy and molly live together?

Guppy fish and molly fish can live together.

Guppies and mollies are non-aggressive fish and do great with other compatible tankmates.

However, mollies can sometimes create some issues by nipping at guppy’s colorful fins, but this will be in rare conditions.

Guppies and mollies are omnivore fish and need plant and meat matter food in their diet.

Same dietary need results in competition for food, so regular monitoring is essential for ensuring all guppies and mollies are getting food.

Guppies and mollies have similar water parameters requirement.

So, from all the above information, we can see that guppies and mollies can live together.

Let us now discuss more in depth about guppies and mollies and what things we should take care of when planning to add mollies to our guppies aquarium.

Also read: Can Guppies Live With Betta Fish?

Guppy and molly ideal water parameters

Water temperature72-82 °F75-82 °F
Water pH level6.8-7.86.8-7.8
This table shows the ideal water parameters of guppy and molly fish.

Guppy requires a water temperature between 72-82 °F

Provide the water pH level between 6.8-7.8 to your guppies.

Molly fish requires a water temperature between 75-82 °F

Provide the water pH level between 6-8-7.8 to your molly fish.

We can conclude from the above information that guppy and molly require the same water conditions to thrive.

You don’t have to change the water parameters when planning to add molly fish to your guppies aquarium.

Guppy and molly dietary requirements

Guppy-Molly FoodServing QuantityNo of Times
Veggie pelletsOne pinch at a time2-3 times a day
Mosquito larvae10-15 pieces2-3 times a week
BloodwormOne pinch at a time1-2 times a week
Tubifex WormsOne pinch at a time1 time a week
Zucchini (Blanched)One small slice3-4 times a week
Brine shrimpOne pinch at a time1-2 times a week
This table shows the dietary requirements of guppy and molly.

Guppies and mollies are both omnivore fish species.

They both require plant and meat matter in their diet.

You can feed your guppies and mollies, veggie pellets, and flake food.

To ensure their faster growth and healthy lifespan, you should serve various foods to your guppies and mollies.

You must know that guppies and mollies love to eat bloodworms.

But, you should feed bloodworm to your guppies and mollies as a treat once a week as bloodworm contains a high percentage of fat.

Feeding your guppies and mollies live food will do great in their faster growth and enhance your guppy’s color.

Live food like mosquito larvae, brine shrimp, tubifex worms, etc.

If you don’t have access to live food, you can feed them freeze-dried bloodworm, brine shrimp, tubifex worms, etc.

Feed tubifex worms only once a week to your guppies and mollies.

Add plant matter food to your guppies and mollies diet.

Feed them blanched vegetables and live plants, and growing algae will also help provide plant matter food to your guppies and mollies.

Guppies and mollies will only nib at your live aquatic plants, not causing any severe damage to plants.

So, you can add plenty of live aquatic plants to your guppy-molly aquarium.

Also read: Best Homemade Food For Guppies

Guppy and molly temperament.

Knowing the temperament of fish before adding it to your aquarium is essential.

Being aware of guppy and molly temperaments will help you detect the issue in your fishes when they show strange behavior.

Guppy temperament

Guppies are peaceful fish species and love to live in a community tank.

Guppies are non-aggressive and will not create any issue with mollies.

However, some conditions can trigger aggressiveness in your guppies, like illness, stress, and an improper ratio of male and female guppies.

If you have more male guppies in your tank and few female guppies, it can be a reason for aggressiveness in the male guppy.

Male come will fight each other to mate with the female guppy.

Also, more male guppies and a few female guppies will make your female guppy come under stress because of the constant chasing of male guppies for reproduction.

Consider keeping the guppies in the ratio of 2:1.

Keep two female guppies for one male guppy.

You can also go for keeping three female guppies for one male guppy.

Molly temperament

Molly fish are also a peaceful species and do great in a community tank.

Mollies will not be aggressive until you provide them with good living conditions and a big enough space to swim freely.

Mollies will show signs of aggression when you keep them in an overcrowded tank or with other aggressive tankmates.

Why molly will be aggressive, it will target guppies because of their smaller size and colorful fins.

Mollies need big enough space for their happy and healthy lifespan.

How can we keep guppy and molly together?

Keeping guppies and mollies together is not a difficult task.

However, there are some precautions you have to take when adding mollies to your guppies aquarium:

  1. Keep your guppies and mollies in a large size tank.
  2. Create plenty of hiding places for mollies and guppies.
  3. Add lots of live aquatic plants to your guppy-molly tank.
  4. Monitor feedings carefully.
  5. Control population of guppies and mollies.
  6. Protect your guppy and molly fry
  7. Perform a regular water change

Large size tank

Mollies and guppies both require enough space to live comfortably.

Mollies are peaceful fish, but if we keep them in the overcrowded tank, they will show signs of aggression.

Mollies will chase and try to hurt guppies by nipping their fins in aggression.

So, for not letting this happen, keep your mollies and guppy in a large enough tank where they can live and swim freely.

Follow one inch one gallon rule, one inch of fish per one gallon of water.

Mollies can be 4 inches long, whereas guppies can be 2.4 inches long.

So, if you have 20 gallon tank, consider keeping three guppies and two mollies.

Someplace will be covered by plants, substrate, and other decors.

Also read: How Many Guppies In A 20 Gallon Tank?

Control population 

Guppies and mollies are both life bearers.

If you keep male and female guppies together in the same aquarium, they will breed out of control.

Guppies and molly can get pregnant every 30 days. 

Because they both can get pregnant right after releasing fry and the gestation period of mollies and guppies is 30 days. 

Pregnant female guppy can give birth to 5-120 fry at a time. 

Pregnant female guppy can also give birth to 5-70 fry at a time.

Guppies and mollies can carry sperm with themselves and can be pregnant multiple times.

Mollies can use the sperm for three months to get pregnant multiple times.

Whereas guppies can use the sperm to get pregnant multiple times for a lifetime.

Adding only female molly and guppy to your aquarium also has possibilities of them getting pregnant because of previous encounters with male molly and guppy.

So, controlling the population becomes essential when keeping mollies and guppies as they can get your aquarium overcrowded. 

Keeping only one gender for each molly and guppy also will not solve the problem of population control. 

Guppies and mollies can reproduce with each other when they don’t find the opposite gender in their species. 

If you cannot control the population of molly and guppy, you have to keep only male guppy and molly or only female guppy and molly.

Also read: Can Guppy Fry Survive In A community Tank?

Add lots of live aquatic plants.

Consider adding lots of live aquatic plants to your guppy-molly tank.

Plants will help the fry to hide from adult tankmates.

Also, plants keep the tank well oxygenated and clean.

Guppies and mollies need plant matter food to thrive, which you can help them provide by adding lots of live aquatic plants.

You can add these plants to your guppy-molly aquarium:

  1. Java fern
  2. Java moss
  3. Duckweed
  4. Water sprite
  5. Hornworts
  6. Amazon frogbit
  7. Elodea

Also read: Does Guppy Eat Plants?

Create hiding places

Guppies and mollies are usually found in streams and rivers in their natural habitat.

These places are packed with plants and hiding places.

Hiding places help them to keep themselves safe.

So, providing plenty of hiding places will make them live comfortably in an aquarium. 

Protect guppy and molly fry

Guppy and molly are life bearers and give birth to fry.

Guppies and mollies don’t have a parental instinct and will happily eat their fry.

Guppy and molly will eat their fry after giving birth.

If you want to protect your guppy and molly fry, then you can do three things:

  1. Keep the guppy and molly fry in the breeding box.
  2. Keep the guppy and molly fry in a separate tank.
  3. Create hiding places by adding lots of aquatic plants and other hiding decors.

Make sure not to keep guppy and molly fry for too long in the breeding box, as it will affect their growth and health.

Also, don’t keep the pregnant molly or guppy in a breeding box because it can cause stress to them, and they can abort the fry. 

Separate the pregnant guppy and molly from their fry right after they give birth to them. They will eat their fry otherwise.

If you are moving your pregnant guppy and molly to a separate tank, make sure to adjust the water parameters as before for your pregnant fish.

Perform a regular water change

More breeding will result in more molly and guppies in your tank.

Usually, molly and guppy will eat the fry, but there will be some fry that will save themselves and grow.

So, more mollies and guppy will be there with time.

More population will result in more production of waste.

So for keeping your aquarium clean, you have to perform a water change regularly (30% weekly).

You can also add a good filtration system with biofilter media to keep your aquarium free from nitrates and ammonia. 

Also read: Do Guppies Need Filters?

Monitor feedings carefully

Guppy and molly fish are omnivore fish species and require both meat and plant matter food in their daily diet.

Guppies and mollies have similar dietary requirements.

Similar food requirements will result in guppies and mollies competing for food.

So, you have to regularly monitor while feeding that all your guppies and mollies are eating. 


Guppy fish and molly fish can live together as they are non-aggressive fish and have similar tank requirements. However, Guppy and mollies are omnivore fish species with similar dietary needs, which can trigger competition among them for food. So, regular monitoring while feeding is essential.

Mollies can get aggressive when being kept in an overcrowded tank, making guppies their target, chasing them, and nipping at their colorful fins. So, ensure to keep your guppies and mollies in a big size aquarium.

Reference: ResearchGate, ScienceDirect, Oxford Academic, Wikipedia,

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