Black Molly

 Quick Care Facts

• Care Level: Easy   • Temperament: Peaceful   • Maximum Size: 4"
• Minimum Tank Size: 20 gallons   • Water Conditions: 75-82° F, KH 10-25, pH 7.5-8.5
• Diet: Omnivore   • Origin: Central America   • Family: Poeciliidae
• Species: Mollies   • Aquarium Type: Community

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The Black Molly is a peaceful and flexible fish species that originates from Mexico & Central America. Black Mollies are somewhat unique in their ability to live in both freshwater and saltwater if acclimated slowly over time. They come from areas with very hard water, so they should be provided with a teaspoon of salt per gallon added to their freshwater environment to provide them optimal conditions.

Black Mollies are known for both their brilliant black coloration and their prolific breeding habits that have mated pairs spawning roughly every 45 to 60 days. Overall a great fish for beginning hobbyists and more advanced hobbyists who are looking for an active swimming fish with a striking black coloration.

Black Mollies should be kept in a tropical community aquarium setup with warm water temperatures (78 to 82) and plenty of live plants. While they are a very hardy species that can adapt to a range of environments, Black Mollies prefer hard water with lots of vegetation. A teaspoon of salt per gallon is recommended for community aquariums housing Mollies and is beneficial to other community species as it helps to prevent ich and some other common diseases.

Overall Black Mollies are very peaceful and can easily coexist with just about any freshwater community species. To prevent unwanted babies many aquarists keep either males or females in their aquarium. Male Mollies can be distinguished by their larger top fins and more narrow elongated anal fins, while the females have finnage which is more rounded and blunt.

However, if a mix of females and males are kept together in a community aquarium environment most of the babies will be eaten by the Molly parents and other tank mates which will keep their numbers in check.

The Black Molly is very easy to feed, as it will readily accept a wide variety of meaty and plant based foods. It is best to provide them with both meaty items, vegetable matter and algae. A balanced diet will help maintain both the immune system and the overall health of the fish. Black Mollies will accept flake, freeze dried and frozen foods along with live foods and small pellets and wafers.

In the case of the Black Molly, it is not about what conditions are needed for breeding or how to get them to breed as it how to get them to stop. Mollies in general (with the Black Molly being no exception) are very prolific breeders that if a male and female are present will breed in time. Once breeding, a male/female pair of Black Mollies will birth young every 2 months or so.

The babies should be promptly removed from the aquarium or provided a baby trap, as the parents will eat the young if they are left unprotected. Should the hobbyist aspire to breeding Mollies, and ideal breeding conditions for Mollies include a 30 gallon or larger aquarium, live plants including floating plants and an established algae growth.