Mollies ~ Poecilia sphenops

Mollies are versatile, livebearing fish that come in a variety of colors and fin types, including the popular Black Molly, Sailfin Molly, and Dalmatian Molly. Originating from the coastal and inland waters of Central and North America, these fish can tolerate both freshwater and brackish water, making them exceptionally hardy. Known for their peaceful nature and active swimming habits, Mollies are well-suited to community tanks and make a great choice for aquarists of all experience levels.

- Size: 3-4 inches (some varieties up to 6 inches)  
- Lifespan: 3-5 years  
- Temperament: Peaceful, active  
- Group/Solitary: Best kept in groups, though they are flexible in smaller numbers  
- Food: Omnivorous, flake food, algae, vegetable matter, live/frozen foods (brine shrimp, bloodworms)  
- Water Requirements: 72-82°F, pH 7.5-8.5, moderately hard to hard water, can tolerate brackish conditions

Mollies thrive in well-maintained, planted aquariums with ample swimming space and stable water conditions. They prefer slightly alkaline, hard water and benefit from the addition of a small amount of salt if kept in brackish conditions, although they can thrive in freshwater too. A diet rich in plant matter is essential, so offering algae-based foods along with flakes and occasional live or frozen foods will keep them healthy and enhance their vibrant coloration. They are livebearers, meaning females can give birth to free-swimming fry directly, and if breeding is intended, a heavily planted tank or a separate breeding tank is recommended to protect the young from adult fish.

In the wild, Mollies inhabit coastal streams, estuaries, and brackish areas, which has given them the unique ability to adapt to a wide range of salinities. They are social fish and do best when kept in groups, though they may sometimes display mild aggression, especially among males.

Fun Fact: Mollies are one of the few freshwater fish that can adapt fully to saltwater. Given time and gradual acclimation, they can thrive in marine tanks, making them a unique and adaptable species.