Yes, betta fish—especially the Siamese fighting fish (scientific name: Betta splendens)—are typical tropical freshwater fish. Their survival and health are closely tied to water temperature. Below is a detailed explanation:
1. Tropical Nature of Betta Fish
Origin
Native to tropical regions of Southeast Asia (e.g., Thailand, Cambodia, Laos), where they naturally inhabit warm, still, or slow-moving waters.
Ideal Water Temperature
24–28°C (75–82°F), with an optimal range of 26–27°C (79–81°F).
Below 20°C (68°F), bettas will gradually become less active and refuse food.
Prolonged exposure to temperatures below 18°C (64°F) may lead to death.
Poor Cold Tolerance
Bettas cannot adapt to low temperatures. A heater is required to maintain a constant temperature in winter.
Do not house bettas with cold-water fish (e.g., goldfish).
2. Key Traits of Tropical Fish (Applied to Bettas)
Metabolism Relies on Warmth
As ectothermic (cold-blooded) animals, bettas’ digestion and immune systems are suppressed in low temperatures, making them prone to diseases like ich (white spot disease) and saprolegniasis (water mold).
Breeding Temperature Needs
A stable water temperature of 26–28°C (79–82°F) is required during the breeding season. Without this, bettas may stop laying eggs, or the eggs may fail to hatch.
3. Care Recommendations
Heating Equipment
Use a 25W–50W aquarium heater (size depends on tank volume), paired with a thermostat to prevent temperature fluctuations.
Simulate Natural Habitat
Add almond leaves (to adjust pH to slightly acidic levels) or aquatic plants to mimic the betta’s native tropical environment.
Tankmate Considerations
Avoid housing bettas with aggressive tropical fish.
Compatible tankmates include gentle species like tetras and corydoras catfish.
4. Common Misconceptions
“Bettas Tolerate Low Temperatures”
While bettas may survive short periods of low temperatures, long-term exposure shortens their lifespan or causes chronic illnesses.
“No Heater Needed”
If room temperature consistently stays below 24°C (75°F), a heater is mandatory. Without it, bettas are at high risk of fin rot and dropsy (pinecone disease).
Conclusion
Bettas are classic tropical fish that require constant water temperature for proper care. To keep bettas healthy, a heater is an essential piece of equipment—and maintaining stable water temperature is the key!