Black Lyretail Molly 101: A Comprehensive Beginners Guide

The Black Lyretail Molly is a stunning fish popular among beginner fish enthusiasts for its hardiness and attractive looks. This comprehensive guide will delve into everything you need to know about caring for and keeping lyretail black molly fish in your aquarium.

From its origins to its physical characteristics, we will explore the background of this beautiful fish and how to differentiate it from other Molly varieties.

We will also discuss the ideal tank setup, water parameters, and the appropriate diet and feeding schedule for Black Lyretail Molly.

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Furthermore, we will cover common health issues, potential diseases that can affect this species, and tips for maintaining a healthy and thriving aquarium environment for these fish.

Whether you are a seasoned fish keeper looking to add Black Lyretail Sailfin Molly to your collection or a beginner just starting in the hobby, this guide will provide you with all the essential information you need to care for these captivating fish successfully. 

Black Lyretail Molly Fish Species profile

The Black Lyretail Molly, with its sleek black body and stunning lyre-shaped tail fin, is a captivating freshwater fish that will turn heads in your aquarium.

Black lyretail Molly’s scientific name: 

The lyretail black molly, scientifically known as Poecilia latipinna, is a popular freshwater aquarium fish known for its striking black coloration and distinctive lyre-shaped tail. Native to the southern United States and Mexico, this species is also found in the wild in various freshwater habitats, including ponds, marshes, and streams.

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  • Color: Velvety black with shimmering scales, sometimes with hints of blue or green. The fins may have orange or yellow markings, particularly the dorsal fin, which extends into a dramatic sail-like shape. 
  • Tail Fin: The most striking feature is the large, beautifully forked tail fin, resembling a lyre in shape. This fin can be up to half the length of the body.
  • Size: Females typically grow larger than males, reaching up to 4 inches, while males stay around 3 inches.


  • Peaceful: Black Lyretail Mollies are generally friendly fish and get along well with other community fish of similar size and temperament.
  • Social: They’re social creatures and thrive in groups. Aim for two females to 1 male to avoid male aggression.

Habitat and Care:

  • Tank Size: A minimum 20-gallon tank is recommended for a small group of Black Lyretail Mollies.
  • Water Parameters: Prefer warm water temperatures (78°F-82°F) and slightly hard water with a pH range of 7.5 to 8.5.
  • Diet: Omnivorous, enjoy a varied diet of flakes, pellets, brine shrimp, and blanched vegetables.
  • Aquarium Setup: Provide plenty of hiding places with live or artificial plants and rocks. Good water filtration is essential.


  • Livebearers: Black Lyretail Molly is a livebearer fish, meaning they give birth to free-swimming fry.
  • Fry Care: Separate pregnant females into a breeding tank or net to protect the fry from being eaten. Fry can be fed crushed flakes or brine shrimp.

Overall, Black Lyretail Mollies are:

  • They are Hardy and easy to care for, making them suitable for beginner aquarists.
  • Active and playful, adding a splash of personality to your tank.
  • They are relatively affordable and readily available, making them popular for aquarium enthusiasts.

With their striking appearance and peaceful nature, Black Lyretail Mollies will be a welcome addition to your freshwater aquarium.

How can you tell if a black lyretail is male or female?

 Like many other molly species, the black lyretail mollies can be distinguished by their physical characteristics to determine their gender. Sexing black lyretail mollies can be tricky, but there are a few reliable methods:

1. Anal fin: The most definitive way to tell the sex of a lyretail black molly is by looking at the anal fin. In males, the anal fin is modified into a gonopodium, which is a tube-like extension used for internal fertilization. In females, the anal fin is shorter and rounded.

2. Genital papilla: Located near the base of the anal fin, the genital papilla is a small, fleshy protrusion. In males, the papilla is pointed and directed forward. In females, the papilla is rounded and runs backward.

3. Dorsal fin: The male black lyretail mollies often have larger dorsal fins and are more pointed than females’ fins.

4. Size and body shape: Male black lyretail mollies are generally slightly smaller and slimmer than females. However, this is not a foolproof method, as some females can be pretty large.

5. Behavior: Male black lyretail mollies tend to be more active and chase females around the tank. Females are more passive and spend their time feeding and hiding.

Here are some additional tips for sexing black lyretail mollies:

  • Look at a group of fish together. It can be easier to spot the differences between males and females when you have them side-by-side.
  • Use a flashlight. Shining a light through the fish’s body can help you see the internal organs, which can sometimes give you a clue about the sex.
  • Consult a fish expert. If you still need to figure it out, it’s always best to consult with a fish expert at your local pet store or aquarium.

Observing these physical characteristics makes it possible to determine the gender of a black lyretail molly with reasonable accuracy.

What community fish can live with golden black lyretail molly?

Golden black lyretail mollies are peaceful fish, but their lively temperament and moderate size require careful consideration when choosing tank mates. Here are some compatible community fish for your mollies:

Peaceful and similar in size:

  • Neon tetras: These small, colorful fish are active and peaceful, making them excellent tank mates for mollies.
  • Harlequin rasboras: These tiny, shimmering fish are a great addition to a community tank and will stay out of the way of your mollies.
  • Corydoras catfish: These bottom-dwelling catfish are peaceful scavengers and will help keep your tank clean.
  • Dwarf gouramis: These elegant fish are peaceful and relatively shy, making them good tank mates for mollies.
  • Cherry barbs: These active fish are fast enough to avoid being nipped by the mollies and will add color to your tank.

Slightly larger but peaceful:

  • Honey gouramis: These delicate fish are slightly larger than mollies but are still gentle and community-friendly.
  • Bolivian rams: These peaceful and relatively shy cichlids make them good tank mates for mollies.
  • Angelfish: While angels can be territorial, they can coexist peacefully with mollies if there is enough space and hiding places in the tank.

Aquarium water conditions for black lyretail mollies

Black lyretail mollies are freshwater fish that require specific water conditions to thrive in an aquarium. The ideal water temperature for these mollies is between 75-82°F (24-28°C), and the pH level should range from 7.5 to 8.5.

It is crucial to maintain good water quality by regularly testing and monitoring the ammonia, nitrite, and nitrate levels. Black lyretail mollies are sensitive to high ammonia and nitrites, so keeping these levels at a minimum is essential.

Additionally, these mollies prefer a well-aerated aquarium with moderate water flow. It is recommended to provide them with a well-planted tank with plenty of hiding spaces to mimic their natural habitat. It is essential to perform regular water changes to remove accumulated waste and maintain the overall water quality.

By providing the proper water conditions and maintenance, black Sailfin mollies can live a healthy and vibrant life in the aquarium.

How do you breed black lyretail Molly Aquarium Fish for profit?

Breeding black lyretail molly fish can be a rewarding and profitable hobby. Still, it’s essential to research and ensure you’re providing proper care for your fish throughout the process. Here’s a general guide to get you started:

Setting up the breeding tank:

  • Tank size: Start with a tank of at least 10 gallons for a breeding pair, and add 5 gallons for each additional female. A larger tank will provide more space for the fry (baby fish) to grow and prevent overcrowding. 
  • Water parameters: Maintain stable water parameters suitable for mollies. Aim for a pH between 7.5 and 8.2, a temperature of 78°F to 82°F, and hardness around 15 dGH.
  • Filtration: Use a sponge filter or another gentle filtration system to avoid harming the fry.
  • Decoration: Provide some hiding places for the fry, such as live plants or aquarium decorations. Avoid using gravel, as fry can get trapped and suffocate.

Selecting breeding stock:

  • Choose healthy, mature fish that are at least six months old.
  • Look for fish with good finnage and vibrant colors, as these traits will likely be passed on to their offspring.
  • Maintain a ratio of one male to two or three females.

Breeding process:

  • Once the breeding tank is set up and the fish are acclimated, condition them with high-quality food. Brine shrimp and bloodworms are good options.
  • Keep the lights on for 12-14 hours daily to stimulate breeding.
  • The males will chase and harass the females, which is normal behavior. If the females seem overly stressed, you can separate them for a while.
  • The females are livebearers, meaning they give birth to free-swimming fry. They can produce fry every 4-6 weeks.

Caring for the fry:

  • Remove the parents from the breeding tank after the fry is born to prevent them from eating their young.
  • Feed the fry small amounts of food several times daily, such as infusoria, baby brine shrimp, or powdered fry food.
  • Keep the water quality high by performing regular water changes.
  • As the fry grows, you can gradually increase the water hardness and salinity to match the main tank.


  • Black lyretail mollies are generally considered easy to breed and can be sold for a few dollars each. However, the profit margin can be small, especially when considering the costs of food, equipment, and electricity.
  • It’s essential to have a reliable market for your fish before you start breeding on a large scale. Potential buyers can be local fish stores, online marketplaces, and aquarium clubs.

Additional tips:

  • Be patient. It may take several weeks for the fry to reach a sellable size.
  • Refrain from overcrowding your tanks. Overcrowding can lead to poor water quality and disease.
  • Quarantine any new fish before adding them to your breeding tanks to prevent the spread of disease.
  • Research and learn as much as you can about breeding mollies before you start. There are many resources available online and in books.

Remember, breeding fish should be a hobby first and foremost. It’s essential to prioritize the well-being of your fish and not focus solely on profit. With proper care and planning, you can enjoy the satisfaction of breeding beautiful lyretail black sailfin molly fish and potentially make a little money on the side.

What does gold-black lyretail molly Eat?

Gold black lyretail molly species are omnivores, enjoying a varied diet of algae, zooplankton, brine shrimp, and even some flake food. Their vibrant colors shine brightest with a balanced plant and animal matter mix.

Are lyretail black mollies aggressive?

Lyretail mollies are generally peaceful. However, individual temperament may vary. Providing ample space, hiding spots, and a well-balanced community can help prevent aquarium aggression.

Can a Black Molly live in a 10-gallon tank?

While a single Black Molly can technically survive in a 10-gallon tank, it’s not ideal. They thrive with more swimming space and prefer fish tanks closer to 20 gallons. Consider a smaller species like a Dwarf Molly for a 10-gallon setup.

How big do black lyretail molly fish get?

Black lyretail mollies grow around 2.5-4 inches long, with females reaching slightly larger sizes than males. Their signature lyre-shaped tail fin can add an extra inch or two to their overall length.

Is black balloon molly lyretail fish friendly?

Black balloon molly lyretail fish are generally considered friendly and peaceful community fish. They’re playful and active swimmers, and their vibrant black bodies with extended lyre-shaped tails add a striking splash of color to any aquarium.

How do you identify Male and Female Black Lyretail Molly?

Spotting the differences between male and female Black Lyretail Mollies is easy! Males flaunt a larger, more colorful lyre-shaped tail fin, while females have a smaller, less dramatic tail and a rounder body. Additionally, males often display a bright anal fin used for mating.

Are black lyretail mollies good algae eaters?

Black lyretail mollies are omnivores and nibble on some algae but are not dedicated algae eaters. Consider species like shrimp, snails, or algae-eating fish like Otocinclus for effective algae control.

Do mollies need salt in their water?

No, mollies don’t require salt in their water! They’re freshwater fish, naturally thriving in rivers and lagoons. While some hobbyists add a little aquarium salt to replicate their native brackish environments, it’s not essential for their health. Too much salt can be harmful.


In conclusion, the vibrant and graceful lyretail black molly is a captivating addition to any aquarium. Its striking black coloration, flowing fins, and graceful movements make it a standout among freshwater fish enthusiasts. Whether you’re a beginner or an experienced aquarist, this beautiful species offers endless joy and wonder. So, if you want to add a touch of elegance and beauty to your aquatic habitat, don’t hesitate to consider the black lyretail molly. Its unique charm and mesmerizing presence make it a stunning centerpiece in your tank.

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About Me

I am the founder of, a devoted wife and mother, and an avid fish enthusiast. My aim is to assist fellow fish lovers worldwide in understanding how to properly care for and breed their pet fish.

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