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Freshwater Fish

Balloon Molly

A round-bellied, gentle livebearer that greets you at the glass and never hides.

Poecilia sphenops
Available for local pickup by appointment only.

Balloon Mollies are the friendliest fish in the livebearer family — compact, round-bodied, and endlessly curious. They swim out front of the tank all day, graze algae and biofilm off every surface, and breed readily in healthy water. Extremely hardy and forgiving, they are one of the best first fish for a new aquarium and thrive in hard, alkaline tap water.

Reference image — cultivar may vary.Imagen de referencia — el cultivar puede variar.

Photo: Foto: Representative product image

Care Sheet

What it needs to thrive

Lighting
Low to moderate. Floating plants and darker substrate help these fish display their best color.
Flow
Gentle to moderate with open swimming room and planted cover along the edges.
Feeding
Small quality flakes or micro pellets daily, supplemented with frozen baby brine shrimp, daphnia, or bloodworms.
Temperament
Peaceful schooling fish. Keep at least 6, with 8 or more preferred for natural behavior.
Difficulty
Beginner
Ideal Tank Size
20 gallons and up for a small group.
Water Parameters
72–82°F · pH 7.0–8.2 · hard, alkaline water · 0 ammonia / 0 nitrite
Placement

Anywhere in a community tank. Give them open swimming space with a few planted margins for cover.

Aggression & handling

Peaceful. Keep one male with two or three females, or all females, to avoid persistent chasing. Never keep with fin-nippers.

freshwater fishlivebearermollyhard-water-packsfreshwater-kids-familylocal pickup
Arrival Protocol

Quarantine, dip, and acclimation

Quarantine

Hold all new fish in a bare-bottom 10–20 gallon QT for a minimum of 4 weeks. Observe for flashing, clamped fins, white spots, or breathing changes. Treat preventatively with copper (1.75–2.5 ppm chelated) or tank-transfer method for ich, plus a praziquantel course for flukes. Invertebrates and corals skip QT but go through dip and observation instead.

Recommended coral dip

For every new coral: a 5–10 minute bath in your reef-safe dip of choice (Bayer Complete, CoralRx, or Reef Primer) following label dosage, followed by two clean saltwater rinses. Inspect plugs and bases for flatworms, pyramid snails, and eggs — remove or refrag onto clean plugs before placing in display.

Acclimation

Float sealed bags in your QT or display for 15 minutes to match temperature. Then drip acclimate at 2–4 drops per second for 45–60 minutes until volume has tripled. Net livestock into the tank — never pour shipping water in. Dim the lights for the first 24 hours to reduce stress.

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