Poecilia sphenops var.
Also known as: Balloon Black Molly, Black Balloon Molly
Origin: Captive bred

The Balloon Black Molly is a captive-bred variant of the common black molly, characterised by the balloon body mutation that causes a pronounced rounding of the abdomen. This gives the fish a distinctive, almost spherical body shape that many hobbyists find charming and entertaining to watch.
The balloon mutation is controversial among some hobbyists as it affects the fish's natural body proportions, but balloon mollies are generally healthy and long-lived when maintained in appropriate conditions. The all-black colouration provides a bold contrast in planted aquariums.
Balloon mollies are peaceful community fish that benefit from slightly brackish water or at least hard, alkaline freshwater conditions. A small addition of aquarium salt (1–2 tablespoons per 10 L) can benefit their health in freshwater setups.
Water: 24–28 °C, pH 7.5–8.5, GH 15–25; benefits from light salt addition (1 tsp/10 L optional). Tank: 80 L minimum; avoid strong currents that stress the balloon body form. Feeding: Quality flake, spirulina wafers, blanched vegetables; 2–3 meals daily. Breeding: Livebearer; 20–60 fry per brood; balloon trait is inherited in some offspring. Compatibility: Peaceful community fish; ideal with mollies, platies, and swordtails.
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