Freshwater Mollies

Freshwater Mollies

Stunning and simple - bring colour, movement and personality to your tank with our diverse range of Mollies.

Mollies are hardy tropical freshwater fish that come in an impressive range of colours and patterns. They are generally peaceful and confident swimmers, though they may nip fins if housed with the wrong tankmates. Most Mollies prefer the mid to upper levels of the tank and enjoy schooling with their own kind.

Mollies are also prolific livebearers, making them an excellent choice for hobbyists interested in breeding. While most varieties share similar body shapes, Sailfin Mollies are the major exception, known for their tall, dramatic dorsal fins.

Molly Care

Mollies are easy to maintain and tolerate a broad range of water parameters, making them ideal for a fish tank setup for beginners. However, they can be prone to certain illnesses, so it's important to follow a quarantine routine before adding them to a community setup.

It is useful to keep some treatment medications on hand. Keeping classic Black Mollies can make it easier to spot early signs of white spot disease, which can be treated with a white spot remedy.

With proper care, a molly may live for around five years and reach up to 15 cm (6”), though this size is uncommon. As shoaling fish, they should be kept in groups of at least four, with more females than males to limit aggression. Some of our most popular varieties include the Dalmatian Molly, Black Lyretail Molly, Silver Molly and assorted Balloon Molly packs.

Different Molly species can interbreed, so expect a range of unique variations to appear naturally in the tank over time.

Mollies Natural Habitat

Wild Mollies are found throughout the southern United States, Central America and northern South America, with a strong presence in Mexico. They typically inhabit slower-moving rivers, streams and sometimes brackish waters.

Behaviour & Compatibility

Mollies are usually friendly but may occasionally nip fins. Avoid mixing male Mollies with long-finned species such as Fancy Goldfish and Angelfish. Groups with too many males may also harass females, so a ratio of two or three females per male is recommended.

They are mid-water to surface swimmers and tend to explore in groups when young, before becoming more independent with age. Suitable tankmates include Danios, peaceful Barb species, Tetras and Corydoras.

Mollies Fish Tank Set-up Tips

• Tank

  Although smaller fish, Mollies are active and social, requiring a reasonably sized tank. A group of at least four is recommended. Most varieties reach around 7 cm (3”), while dwarf types grow smaller and Sailfins grow larger. If keeping Sailfin Mollies, ensure your tank is suitably sized. Longer tanks are preferred over tall ones to accommodate their swimming behaviour.

  Recommended Max Fish Count	Tank Volume
  4 Mollies	45 litres (12 gallons)
  8 Mollies	68 litres (18 gallons)
  12 Mollies	92 litres (26 gallons)
  15 Mollies	128 litres (34 gallons)

• Base

  Although they spend most of their time mid-water, Mollies often explore the bottom of the tank among plant roots and décor. A soft sand substrate helps prevent scrapes, especially for larger Sailfin types.

• Foliage

  Even though Mollies enjoy open water, offering a few hiding and resting spots helps reduce stress and encourages natural behaviour. Live or artificial plants, driftwood and decor with caves or swim-throughs work well.

• Water

  Mollies tolerate varied water conditions and do not require added salt. Fish raised in higher salinity may struggle in pure freshwater, but none of our stock requires brackish care. They prefer 22-30°C (71-85°F). Depending on your climate, you may need a water heater to maintain this range.

  Aim for a pH of 5.5-8 and a hardness of 1-15 dGH. A reliable testing kit will help monitor these levels. Maintain a consistent filtration system and perform regular water changes (10% weekly or 25% fortnightly). The substrate should also be cleaned regularly, and any tap water used should be treated with suitable water conditioners.

Feeding and Care

Mollies are omnivores and need a mix of plant and animal matter, with a slight preference for meat-based options. Quality flakes are a great staple, supported by regular live or frozen foods such as brine shrimp, bloodworms and daphnia. Vegetables like lettuce, cucumber and zucchini can also be offered in moderation. Explore our range of fish food to find suitable feeding options.

Great Reasons to Keep Mollies

• Active swimmers that bring colour and movement to a community tank.
• A fantastic introduction to livebearing and breeding.
• Low-maintenance fish that work well alongside more delicate species.

Have a look through our full range below and choose the Molly variety that suits your setup & whether you prefer large Sailfins or the charm of a variety Balloon Molly, there's something for every aquarium.