Black Sailfin Molly

Sailfin Molly (Poecilia latipinna / Poecilia velifera)

The Sailfin Molly is one of the most celebrated and visually striking livebearers in the aquarium hobby. It is best known for the large, impressive dorsal fin displayed by males, which gives this species its name. Decades of selective breeding have produced an incredible range of colour varieties, including black, green, dalmatian, golden, harlequin (calico), chocolate, albino, creamsicle, and many more.

Although Sailfin Mollies originated in freshwater, brackish, and even marine environments across southern North America, modern tank-bred specimens are almost exclusively raised in and thrive in alkaline freshwater aquariums. Growing to around 10–12 cm (4–5 inches) as adults, they are considered large compared to many community fish, yet they maintain a peaceful and outgoing nature that makes them an excellent addition to mixed-species tanks.

Behaviour & Compatibility

Sailfin Mollies are compatible with most peaceful aquarium species when kept in a suitably sized tank. As omnivores, they may prey on very small dwarf shrimp or shrimp fry, but they are otherwise safe with peaceful invertebrates. They are active swimmers that primarily occupy the middle to upper levels of the aquarium.

This species is capable of jumping, particularly during the initial acclimation period, so a secure lid is strongly recommended.

Feeding

Sailfin Mollies are not picky eaters. They readily accept high-quality dry foods such as flakes or pellets, which should be supplemented with frozen foods. Diets high in plant matter help support digestion, health, and vibrant colouration.

Plants & Aquascaping

Live plants are not essential, but they are appreciated. Hardy stem plants, rooted plants, mosses, and Marimo Moss Balls are all generally safe when the fish are well fed. Their adaptable nature makes them suitable for both planted and lightly decorated aquariums.

The Sailfin Molly is an excellent choice for both beginners and experienced aquarists.

What We Like About This Fish

• Hardy and adaptable

• Stunning variety of colour forms

• Peaceful and outgoing temperament

• Excellent for medium to large planted aquariums

Recommended Tank Parameters

• Temperature: 22–26.7°C (72–80°F)

• pH: 7.0–8.5 (7.5 or higher is ideal)

• KH: 15–35 dKH

• Minimum tank size: 10 gallons for a single fish, 30+ gallons for a group

Care Guidelines

• Diet: High-quality flake foods and frozen foods, especially those high in plant matter

• Social behaviour: Shoaling; peaceful with most species

• Origin: Tank-bred; native to southern North America, including Mexico

• Average adult size: Males up to 12.7 cm (5 inches), females up to 10.2 cm (4 inches)

• Average purchase size: 2.5–7.5 cm (1–3 inches)