Balloon Molly

Poecilia latipinna hybrid

Livebearers

A selectively bred morphological variant characterized by a shortened spine and a rounded, balloon-like belly. Due to their altered anatomy, they are poorer swimmers than standard mollies and are prone to digestive and swim bladder issues. Like all mollies, they thrive in hard, alkaline water, appreciate algae in their diet, and are highly tolerant of brackish conditions.

Balloon Molly At a Glance

Adult Size7 cm
Body ShapeGlobular
Growth RateModerate
TemperamentMostly Peaceful
Water TypeBrackish Tolerant
Flow PreferenceLow
Waste OutputHigh
StockingGroup of 3+

Balloon Molly Tank Requirements

Minimum Volume75 L
Minimum Length60 cm
FlowLow
Water TypeBrackish Tolerant
Must-Haves in the Tank
Established Algae (Otocinclus)Plants - Densely covered
Stocking calculator

Will Balloon Molly fit in your tank?

Care guides tell you what Balloon Molly needs, the next question is whether your tank can safely provide it. Test Balloon Molly against your tank size, maintenance needs, and the fish you already keep before you buy.

Balloon Molly
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Balloon Molly Water Parameters

Temperature2428°C
pH78.5
Hardness1225 dGH

Balloon Molly Temperament & Compatibility

Aggression LevelMostly Peaceful
3/10
Where They Swim
Surface
Mid-level
Bottom
Stocking Guidelines
Keep at Least3 fish
Max per TankNo limit
Can Live Alone?No — needs a group
Behavior Traits
Hyperactive / Fast SwimmerFry Predator

Balloon Molly Varieties

Each variety inherits the species defaults above. Only differences are highlighted.

Male

Males possess a modified anal fin called a gonopodium. They relentlessly pursue females to mate. It is highly recommended to keep a ratio of at least 2-3 females per male to disperse harassment.

Differs in 2 traits from base species

Also known as: Male Molly

Adult Size6 cm
TemperamentMostly Peaceful

Female

Females are generally larger and more robust. When housed with males, they will be almost constantly pregnant, dropping live fry every 3-4 weeks. Provide dense plants for fry survival.

Differs in 2 traits from base species

Also known as: Female Molly

Adult Size7.5 cm
TemperamentPeaceful

Balloon Molly Care Guide Summary

The Balloon Molly, scientifically known as Poecilia latipinna hybrid, belongs to the Livebearers family group. Adults reach a maximum size of approximately 7 cm and have a globular body shape with a moderate growth rate. Classified as mostly peaceful, this species primarily occupies the surface and mid-level zones of the aquarium and produces a high level of biological waste.

To thrive, the Balloon Molly requires a brackish tolerant aquarium with a minimum volume of 75 litres and a tank length of at least 60 cm. Water temperature should be maintained between 24°C and 28°C, with a pH range of 78.5 and a general hardness of 1225 dGH. A low water flow is preferred.

The Balloon Molly is a rewarding species to keep, provided its core environmental needs are met. This species is available in 2 varieties: Male and Female. Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.

Balloon Molly Habitat Setup

When setting up an aquarium for the Balloon Molly, a low water flow best suits their natural preferences. Because this species occupies the surface and mid-level zones, the aquarium layout should prioritise adequate surface area with floating cover to make them feel secure near the waterline and open swimming space in the centre of the tank for free movement. Useful additions include an established tank with natural algae growth, as they depend on it as a primary food source and dense planting to provide cover, break sightlines, and reduce stress.

Balloon Molly Compatibility Notes

Classified as mostly peaceful, the Balloon Molly is a social species that requires the company of its own kind to thrive. When choosing tankmates, their energetic swimming style may stress more sedentary or timid species. Selecting tankmates that favour different water layers from the surface and mid-level zones can help reduce competition and territorial overlap.

Balloon Molly Recommended Tank Sizes

Standard aquarium sizes that meet the minimum volume and length requirements for Balloon Molly.

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Frequently Asked Questions About Balloon Molly

How big does Balloon Molly get?

Balloon Molly (Poecilia latipinna hybrid) typically reaches a maximum adult size of approximately 7 cm. They have a globular body shape and a moderate growth rate.

What tank size does Balloon Molly need?

A minimum aquarium volume of 75 litres and a tank length of at least 60 cm are recommended for Balloon Molly. This ensures enough swimming space and helps maintain stable water conditions.

What water parameters does Balloon Molly need?

Balloon Molly thrives in brackish tolerant conditions with a temperature range of 24–28°C, a pH between 7 and 8.5, and a general hardness of 12–25 dGH. A low water flow is preferred.

Is Balloon Molly peaceful or aggressive?

Balloon Molly is classified as mostly peaceful with an aggression score of 3 out of 10. They are generally well-suited to peaceful community tanks.

Can Balloon Molly live alone?

No, Balloon Molly should be kept in groups of at least 3 to reduce stress and encourage natural behaviour.

Does Balloon Molly have any special tank requirements?

Yes. Balloon Molly benefits from established algae (otocinclus) and plants - densely covered in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.


Fish Similar to Balloon Molly

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10 cm Mostly Peaceful

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Marbled Hatchetfish

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