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GoldfishVSMolly Fish

Can they live together? Complete Compatibility Analysis

Compatibility Score
25
🚫 Do Not Mix

Goldfish are coldwater fish requiring cooler temperatures and produce high waste, while Mollies are tropical fish requiring warmer, stable temperatures and higher pH/hardness. Their fundamental environmental needs are incompatible.

Potential Issues
  • •Goldfish will be stressed and prone to disease in tropical temperatures.
  • •Mollies will be lethargic, lose color, and be susceptible to illness in coldwater temperatures.
  • •Goldfish are messy eaters and can outcompete Mollies for food, leading to malnutrition for the Mollies.
Tank Requirements
Temperature
Cannot be reconciled. Goldfish: 65-72°F (18-22°C). Mollies: 75-82°F (24-28°C).
pH Level
Goldfish: 7.0-7.5. Mollies: 7.5-8.5 (prefer hard, alkaline water).
Minimum Tank Size
Not applicable for mixing. For species-specific tanks: 30+ gallons for fancy Goldfish, 20+ gallons for Mollies.

About Goldfish and Molly Fish

When considering adding Molly Fish to a tank with Goldfish, it's crucial to understand their specific needs. Goldfish are coldwater fish requiring cooler temperatures and produce high waste, while Mollies are tropical fish requiring warmer, stable temperatures and higher pH/hardness. Their fundamental environmental needs are incompatible.

Key Differences

  • Goldfish: Requires 20 gallons minimum. Usually prefers coldwater water conditions.
  • Molly Fish: Requires 10 gallons minimum. Usually prefers tropical water conditions.

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