Betta FishVSMolly Fish

Can they live together? Complete Compatibility Analysis

Compatibility Score

⚠️ Caution

While their water parameter ranges can overlap, the primary risk is the Betta's aggression, especially towards fish with long, flowing fins (like male Mollies) or fish that are brightly colored. Mollies are active and can be nippy, which may stress or provoke the Betta. This pairing is high-risk and requires careful management.

Potential Issues

•Male Betta fish are highly territorial and may attack Mollies, mistaking them for rival Bettas.
•Molly fish are livebearers and prefer harder, brackish water, while Bettas thrive in soft, acidic freshwater. Long-term health may suffer.
•Active Mollies may outcompete the slower Betta for food.

Tank Requirements

Temperature

75-80°F (24-27°C) - a compromise within both species' ranges.

pH Level

7.0-7.5 - a compromise, not ideal for either long-term.

Minimum Tank Size

20 gallons minimum, heavily planted with sightline breaks.

About Betta Fish and Molly Fish

When considering adding Molly Fish to a tank with Betta Fish, it's crucial to understand their specific needs. While their water parameter ranges can overlap, the primary risk is the Betta's aggression, especially towards fish with long, flowing fins (like male Mollies) or fish that are brightly colored. Mollies are active and can be nippy, which may stress or provoke the Betta. This pairing is high-risk and requires careful management.

Key Differences

Betta Fish: Requires 5 gallons minimum. Usually prefers tropical water conditions.
Molly Fish: Requires 10 gallons minimum. Usually prefers tropical water conditions.

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