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Betta FishVSGoldfish

Can they live together? Complete Compatibility Analysis

Compatibility Score
10
🚫 Do Not Mix

Betta fish and goldfish have fundamentally incompatible environmental needs and behaviors. Bettas are tropical, solitary, and aggressive, requiring warm, still water. Goldfish are coldwater, social, and produce high waste, requiring cool, highly-oxygenated water with strong filtration. Their temperature ranges do not overlap.

Potential Issues
  • •Goldfish require water temperatures (60-74°F) that are too cold for a betta's metabolism, leading to stress, lethargy, and immune system failure in the betta.
  • •Bettas (78-80°F) will be severely stressed by the cooler goldfish temperature. A heater set for the betta will dangerously overheat the goldfish.
  • •Goldfish are messy and produce high ammonia, requiring powerful filtration. Bettas prefer very gentle water flow and can be buffeted or stressed by goldfish-appropriate filters.
  • •Male bettas are likely to attack the flowing fins of fancy goldfish, and even the active, clumsy nature of goldfish will stress the betta.
Tank Requirements
Temperature
No compatible overlap. Betta: 78-80°F, Goldfish: 60-74°F.
pH Level
Betta: 6.5-7.5, Goldfish: 7.0-7.8. Slight overlap possible but irrelevant due to temperature conflict.
Minimum Tank Size
Not applicable for a shared tank. They should be housed separately. Betta minimum: 5 gallons. Single fancy goldfish minimum: 20-30 gallons.

About Betta Fish and Goldfish

When considering adding Goldfish to a tank with Betta Fish, it's crucial to understand their specific needs. Betta fish and goldfish have fundamentally incompatible environmental needs and behaviors. Bettas are tropical, solitary, and aggressive, requiring warm, still water. Goldfish are coldwater, social, and produce high waste, requiring cool, highly-oxygenated water with strong filtration. Their temperature ranges do not overlap.

Key Differences

  • Betta Fish: Requires 5 gallons minimum. Usually prefers tropical water conditions.
  • Goldfish: Requires 20 gallons minimum. Usually prefers coldwater water conditions.

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