Molly Fish Care Sheet
BeginnerPoecilia sphenops · fish
Mollies are hardy, peaceful livebearers ideal for beginners. They thrive in slightly hard, alkaline water and should be kept in groups to reduce stress.
Quick care stats
Adult size3-4 inches
Lifespan3-5 years
Min tank size20 gallons
Water temp72-82°F
pH7.0-8.0
Hardness10-25 dGH
Temperamentpeaceful
Group / schooling3+ (prefer 4-6)
Tank matesOther peaceful community fish such as guppies, platies, swordtails, tetras, and corydoras.
DietOmnivore; feed high-quality flake or pellet daily, supplement with algae wafers, spirulina, blanched vegetables, and occasional live/frozen foods like brine shrimp or bloodworms.
What you need (full setup)
🔧 Aquarium tank (20 gal minimum)Provides stable water conditions and swimming space for a group.🔧 Power filter or canister filterMaintains mechanical, biological, and chemical filtration; rated for tank volume.🔧 Adjustable heater (100-150W)Keeps temperature stable within 72-82°F; essential for tropical fish.🔧 Thermometer (digital or stick-on)Allows daily monitoring to prevent temperature swings.🔧 Fine gravel or sand substrateSmooth texture prevents injury and supports plant rooting; mollies enjoy foraging.🔧 Water conditioner (dechlorinator)Removes chlorine/chloramines from tap water; essential for water changes.🔧 Liquid test kit (pH, ammonia, nitrite, nitrate)Enables precise water quality management; crucial for health.🔧 Live or silk plants + decorProvides hiding spots, reduces stress, and mollies graze on algae and biofilm on plants.
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Common health issues
- Ich (white spot disease)
- Fin rot
- Swim bladder disorders
- Stress from poor water quality or small groups
⚠️ For any sign of illness (not eating, lethargy, swelling, retained shed), see a qualified exotics vet. Care sheets are general guidance only.