There are many interesting facts about Molly fish that fish enthusiasts may not know. For example, do you know that molly fish can hybridize with other fish species meaning that they can produce offspring that are a mix of both parent species? Or that they are livebearers, meaning they give birth to live young.
Not only that, there are many interesting facts about Molly fish, making them unique and popular among fish keepers.
This guide will take you through the most interesting facts about Molly fish that you probably didn’t know.
Molly Belongs to The Poeciliidae Family
The molly fish is part of the Poecilia genus and comes from the Poeciliidae family.
Poecilia is derived from the Greek word “poikilos,” which means “multicolored.” It is named after the Greek term for “colorful” (poikilos). This is because these fish vary considerably in terms of the colors and patterns they display.
The scientific names of molly fish differ depending on their species. The common or short-finned molly, for example, is named Poecilia sphenops.
“Sphenops” comes from the Greek word sphenos, which means “wedge.” This fish’s fins are short and wedge-shaped, giving it its name.
In addition, Poecilia latipinna is the scientific name for the sailfin molly, which is also known as the topsail molly. The term “latipinna” refers to a species’ fin form, and it means “broad fin.”
Finally, the Mexican sailfin molly is labeled as Poecilia velifera by scientists. The scientific name “velifera” refers to the species’ distinctive sailfin.
Molly Fish Come in a Wide Range of Hues
In the wild, the common molly exhibits a dull, silvery color. While their bodies tend to be light gray.
The sides, backs, and dorsal fins of many mollies are dotted with rows of spots. These spots can be so crowded together that they almost become one large pattern.
Molly Fish Have Chunky Bodies
The majority of molly fish have chunky, robust bodies; rounded fins; tall, angular dorsal fins; and pointed heads and jaws.
They also have upturned mouths that are meant to assist them in skimming the top layer of water, which is full of oxygen.
Molly Fish Are 8 to 12 Centimeters Long
Mollies can reach lengths of up to 20 cm in the wild. However, in the aquarium, they only grow to be 8 to 12 cm long.
This small size is one of the reasons they’re such a popular choice for home aquariums.
Molly Fish Are Fast Swimmers
Mollies of every shape and size swim at an identical pace: 1.34 miles per hour (2.1 kilometers per hour).
Molly Fish Have little Weight
This one is difficult to answer since it is small in size. However, this tiny fish’s weight ranges from 0.0005 to 0.0010 lb (0.23 to 0.48 g).
Male and Female Can be Distinguished by Gonopodium
The gonopodium is a fin located on the underside of a fish’s body. It is used to deliver sperm to the female during breeding.
This fin is modified to perform this function and is, therefore, shorter in length than the other fins on a male molly’s body.
It is curved and has a hook-like shape. This type of fin is only found in males.
Molly Fish Can Survive in Brackish Water
Mollies are one of the few fish that can adapt to living in brackish water. This type of water has a higher salt content than freshwater but is not as salty as seawater.
There Are Many Different Varieties of Molly Fish
1. Balloon Molly
This variation is a mix of the Sailfin Molly. It’s spherical or balloon-shaped, with a variety of color combinations to choose from, including black, yellow, and white.
2. Black Molly
This species is helpful in reducing algae growth in your aquarium since they love to eat it. They’re also one of the most active mollies and love to swim in schools.
3. Sailfin Molly
The Midnight Sailfin Molly was produced by crossing a Black Molly with a Sailfin Molly. They’re distinguished for their vibrant hues and prominent dorsal fins.
4. Lyretail Molly
It is also called the lyre-shaped caudal fin, and this variation’s name comes from its lyre-shaped tail.
5. Dalmatian Molly
The Dalmatian variant is named for its color pattern, which looks like those of a Dalmatian dog.
6. Gold Dust Molly
The Gold Dust Molly has a black tail and half of the fish’s body in a golden color.
7. Red Sunset Molly
The Red Sunset variation is a vivid red/orange color throughout the body.
8. White Molly Fish
The scales of this all-white variation have a little iridescence to them, giving the fish a beautiful almost “pearl” sheen.
9. Wild Molly
The entire body of the Wild Molly is a dull silver color.
Mollies Are Not an Endangered Species
The IUCN Red List of Threatened Species does not include the common molly on its list. This means that the species is not currently endangered.
Molly Fish Do Not Live Long
Molly fish are not known for their longevity, with a life expectancy of only three to five years.
In the wild, they may live a bit longer, but it’s now always the case since there are a lot of predators that would love to have a little molly for dinner.
Molly Fish Are Hardy
Mollies can tolerate changes to water quality better than other types of fish. This makes them a good choice for people who are not able to keep their water parameters stable.
Still, it’s important to do regular water changes and keep an eye on the levels of ammonia, nitrites, and nitrates in your aquarium.
Molly Fish Are Livebearers
Instead of laying eggs, molly fish give birth to live fry. The fry will be able to swim and take their first bites within a couple of hours after they are born.
Fry are easy to raise, and you may raise them yourself if you follow their water and feeding needs (because of their tiny size, they can only eat little foods that fit in their mouths).
Molly Fish Multiply Quickly
The mating habits of molly fish are quite varied. If you have male and female mollies in the same tank, they’ll certainly breed.
Also, the female molly can store sperm for months and produce young from single fertilization several times.
So, don’t be surprised if you find your female gives birth to some fry while there are no males in the tank!
Molly Fish Do Not Have Parental Instinct
Mollies are quite poor parents and will not care for their offspring. In fact, the fry is often seen as food by the adult mollies.
This is why it’s best to remove the fry from the tank after they are born or raise them in a separate tank.
Molly Fish Are Omnivores
Molly fish are omnivores since they will consume plant substances as well as crustaceans, insects, and worms.
The nutrition regimen for the molly fish is as follows:
- Blanched veggies
- An occasional high protein snack
- Live or frozen bloodworms
- Brine shrimp
- Flake or pellet that contains a high amount of veggies
If you do decide to give your molly fish real veggies, be sure the vegetable’s skin is soft or the fish will not be able to consume it. To accomplish this, you’ll need to blanch them.
Blanching is a method of boiling or steaming vegetables for a brief amount of time before cooling and serving them to the fish.
Molly Fish Have a Big Appetite
Because they’re active fish, molly fish are voracious eaters. Unfortunately, they’ll eat nonstop and have no concept of when to stop. As a result, be cautious not to overfeed them and give them portions that will fit into 3-5 minutes.
Molly Fish Like a Planted Aquarium
Not only do molly fish like to feed on algae, but they also enjoy eating live plants in the aquarium.
Adding hardy plants like hornwort to your molly fish tank may significantly improve the atmosphere.
Molly Fish Tolerate pH Range of between 7.5 & 8.5
The pH of molly fish tanks should be between 7.5 and 8.5, which is only slightly alkaline.
Mollies are not as sensitive to sudden changes in pH as other types of fish, but it’s still best to maintain a stable environment for them.
Molly Fish Prefer Temperature Between 70 & 80 Degrees Fahrenheit
The molly fish is a tropical fish. This implies that they prefer more heat. The best temperature range for them is between 70 and 80 degrees Fahrenheit.
Keep in mind that excessively chilly water can result in stress and disease in molly fish.
Water that is too hot, on the other hand, can have a detrimental influence on their metabolism causing them to die.
Molly Fish Requires Big Tanks
Molly fish are little, measuring around 5 inches in length. However, they’re a very active species that enjoys swimming in the aquarium.
So, for optimum results, at least 20 gallons of tanks are recommended for these fish or even more for additional success.
Molly Fish Are Community-Friendly Fish
If you keep Molly fish with other peaceful fish in a community aquarium, they will be fine.
However, since mollies are fin-nippers, they should not be kept with fish with long fins.
Additionally, try to keep them away from aggressive species and giant predatory fish, as they may become meals.
Male Mollies Can Sometimes Be Aggressive
If there are no females, the males will become extremely violent towards one another.
If you’re going to keep mollies, or if you already have them and they’re being aggressive towards one another, get some more females so that you can minimize their aggressive behavior.
Also, make sure you have an aquarium big enough to properly support the additional mollies because overcrowding may lead to aggressive behavior.
Molly Fish Cab be Eaten by Large Fish
Molly fish are a favorite meal for much larger freshwater and saltwater fish. So, if you have mollies, don’t be surprised if they start disappearing.
To avoid this, you’ll need to either keep them in a tank with fish that are suitable tank mates or in a species only tank.
Mollies Cay Be Kept with a Variety of Other Species
Because they are typically considered to be community fish, mollies can be kept with a variety of other species.
Some ideal tank mates for mollies include:
- Neon Tetras
- Zebra Danios
- Corydoras Catfish
- Pleco Catfish
- Harlequin Rasboras
- Siamese Algae Eaters
- Otocinclus Catfish
Molly Fish Require High Water Maintenance for Breeding
Molly fish will readily breed in the home aquarium. However, to increase your chances of success, it’s important to maintain high water quality.
This means performing regular water changes and keeping the ammonia and nitrite levels low.
Additionally, you’ll need to provide them with plenty of live plants and hiding places for the fry (baby fish).
Molly Fish Can Have 50 to 100 Fry at a Time
Molly fish can have anywhere from 50 to 100 fry at a time. There are some rare situations where the fish have been known to give a little number, but this is not common.
If you are planning on breeding molly fish, then you should expect to have a lot of fry to care for. It is best to have a plan in place before you start breeding so that you know what you are getting yourself into.
Molly Fish Can Hybridize
Hybridize is a term used to describe the process of two different species of fish breeding and producing offspring.
Molly fish are known to hybridize with other species of fish, such as platies and swordtails.
While this is not necessarily a bad thing, it can be difficult to care for the fry if you are not experienced with breeding fish.
Molly fish are a great addition to any aquarium, and they are relatively easy to care for. They are peaceful fish that get along well with other tank mates, and they come in a wide variety of colors and patterns.
We hope you enjoyed this article on molly fish. If you have any questions or comments, please feel free to leave them below.