Assorted Balloon Molly (Poecilia sp.)

The Assorted Balloon Molly (Poecilia sp.) is a short, round-bellied molly with an arched back, a calm personality and a big appetite. Colors vary from fish to fish (white, gold, black, dalmatian and mixed patterns are all common, and many have tall sailfin dorsals), and the mix in our tank changes with each shipment. They are peaceful, beginner-friendly livebearers as long as they get hard, mineral-rich water. Browse the rest of our freshwater fish and supplies.

Care Guide

• Tank size: 20 gallons or larger for a small group. Balloon Mollies are slow, deliberate swimmers, so gentle filter flow, open swimming room and a few plants suit them best.
• Water: Hard, alkaline water is the key to keeping mollies well: GH 12 to 30 dGH, KH 10 to 25 dKH, pH 7.0 to 8.5, 72 to 82°F. Gwinnett County tap water is very soft (under 1 dGH when we test it), so plan on a GH remineralizer such as Seachem Replenish plus a KH buffer such as Seachem Alkaline Buffer with every water change. Replenish raises GH only, so use both.
• Diet: Omnivores that need plenty of greens. Use a spirulina or algae-based flake like Xtreme Spirulina Flakes as the staple, add Hikari Mini Algae Wafers or a gel food, and offer small meaty foods such as brine shrimp a few times a week. Feed small portions twice a day.
• The balloon body: The round shape is bred in, from a shortened, curved spine. It makes them slower swimmers and more prone to bloating and swim bladder trouble than standard mollies, so avoid overfeeding and keep them away from fast, pushy tankmates.
• Groups: Males chase females constantly. Two or three females per male spreads that attention out and keeps the tank calm.
• Breeding: Livebearers. With males and females together, expect fully formed fry roughly once a month. Adults eat many of them, so dense plants or a breeder box help if you want to raise some.

Specifications

Compatibility

Good tank mates are other peaceful fish that like hard water: platies, swordtails, other mollies such as the Dalmatian Lyretail and 24kt Lyretail, Bristlenose Plecos and nerite snails. Skip fin nippers like tiger barbs and serpae tetras, fast or pushy fish that beat them to every meal, and soft-water species such as neon tetras and rasboras, which want very different water.

Recommended Foods & Supplies

• Xtreme Spirulina Flakes: a plant-heavy daily staple
• Hikari Mini Algae Wafers or Repashy Soilent Green for extra greens
• Seachem Replenish to raise GH in soft tap water
• Seachem Alkaline Buffer to raise KH and hold pH steady
• Fritz GH Test Kit to confirm your hardness

FAQ

Do Balloon Mollies need aquarium salt?
Not as a rule. They tolerate slightly brackish water, but what keeps mollies healthy long term is hard, mineral-rich water: calcium and magnesium (GH) plus steady KH. Salt can't stand in for those minerals.

Can I choose the color, or a male or female?
Colors and sexes are assorted. When you come in for pickup, tell us what you're hoping for and we'll do our best to net fish you love from what's in the tank.

Are they good for beginners?
Yes, with one condition: hard water. In soft local tap water mollies often struggle, so a remineralizer, a KH buffer and a GH test are worth having from day one.

Why does my Balloon Molly look bloated or swim at an angle?
The compact balloon body leaves less room for the gut and swim bladder. Small, plant-heavy meals and clean, hard water help the most. If one keeps floating, tilting or stops eating, bring us a water sample and we'll take a look with you.

Will they breed in my tank?
Very likely, if you have males and females. Fry are born live and fully formed, and dense plants or a breeder box give some of them a chance to grow up.