Molly Care Guide

 

Mollies are active, social, and relatively hardy freshwater fish that come in a wide variety of shapes and colors — including Black, Dalmatian, Sailfin, Balloon, Leopard and Lyretail types. They're livebearers and do well in community tanks or species-only setups.

🏠 Tank Setup

• Tank Size:

  • Minimum: 20 gallons for a small group

  • Larger mollies (like Sailfin): 30+ gallons

• Water Parameters:

  • Temperature: 74–80°F (23–27°C)

  • pH: 7.5–8.5 (prefer alkaline water)

  • Hardness: 12–30 dGH (like hard water)

  • Ammonia/Nitrites: 0 ppm

  • Nitrates: < 40 ppm

• Filtration:
  Use a reliable filter with moderate flow. Mollies are messy and benefit from extra filtration.

• Substrate & Décor:

  • Sand or gravel

  • Live plants (Anubias, Java fern, Vallisneria)

  • Driftwood, rocks, and caves for exploration

• Lighting:
  Moderate lighting; beneficial for plant growth and fish coloration

🧑‍🤝‍🧑 Tank Mates

• Peaceful Companions:

  • Guppies, platies, swordtails

  • Corydoras catfish

  • Tetras (non-nippy types)

  • Snails and shrimp (if tank is well-planted)

• Avoid:

  • Betta fish (possible aggression)

  • Fin-nipping barbs

  • Larger, aggressive cichlids

🍽️ Feeding

• Diet: Omnivorous (with a herbivorous preference)
  Feed a mix of:

  • High-quality flakes or pellets

  • Blanched vegetables (zucchini, spinach, cucumber, peas)

  • Algae wafers

  • Frozen/live foods (brine shrimp, daphnia, bloodworms — use sparingly)

• Feeding Schedule:
  1–2 times per day; feed only what they can eat in 2–3 minutes

👶 Breeding & Sexing

• Livebearers:
  Mollies give birth to 20–100 fry every 30–45 days

• Sexing Mollies:

  • Males: Smaller, slimmer, gonopodium (pointed anal fin)

  • Females: Larger, rounded belly, fan-shaped anal fin

• Breeding Tips:

  • Keep more females than males (1:2 or 1:3 ratio)

  • Use dense plants or breeder boxes to protect fry

  • If you want to raise fry, transfer them to a separate nursery tank

🧽 Maintenance

• Weekly Tasks:

  • 25–50% water change

  • Vacuum substrate

  • Monitor water parameters

• Monthly Tasks:

  • Rinse filter media in old tank water (not tap)

  • Trim and clean plants if needed

⚠️ Common Issues

• Overcrowding:
  Mollies are active and need space — overcrowding leads to stress and aggression

• Fry explosion:
  Mollies breed often — if not separated, the tank can overpopulate quickly

• Health Problems:

  • Ich (white spots)

  • Fin rot

  • Livebearer disease (common in poor-quality or balloon mollies)

• Tip: Adding aquarium salt (1 tsp per 5 gallons) can help reduce stress and support gill function — especially beneficial for mollies.

💡 Quick Tips for Success

• Mollies thrive in slightly brackish water, though it's not required unless breeding or recovering from illness

• Always cycle your tank before adding mollies — they are sensitive to ammonia spikes

• Balloon mollies are genetically modified and may have health issues — avoid them if you want long-lived, robust fish

❤️ Final Thoughts

Mollies are energetic, easy to care for, and come in a stunning array of colors and fin shapes. With proper care, a balanced diet, and a well-maintained tank, these friendly fish can thrive for 3–5 years — and may even surprise you with baby fish!