- Ideal water temp for betta fish: 78°F – 80°F / 25.6°C – 26.7°C. You can have this monitored and maintained with a tank heater with a built-in thermometer.
Betta Fish Water Temperatures
Betta fish are actually not native to the U.S. They are tropical fish found in the warm waters of Southeast Asia. They are used to warm, clean water. The best water temp for betta fish is actually fairly restrictive.
💀 Below 72°F / 22.2°C
Your betta fish will be experiencing near-death if kept in this temperature. After an hour, it is likely your betta fish will wind up dead.
🥶 Below 74°F / 23.3°C
This is too cold for a betta fish. This will cause immune system damage, making them much more prone to unsavory diseases. Cold temperate also slows a betta fish’s immune system down to a crawl. They will eat less if anything at all. A slow metabolism and lack of nutrition also leads to a lethargic state. Signs of lethargy are a decrease in movement, floating on its side, or floating at the bottom of the tank.
😊 Between 78°F – 80°F / 25.6°C – 26.7°C
This is the ideal temperature for your betta fish. Keeping your betta fish in this temperate, along with other proper upkeep, will allow your betta fish to live up to its full lifespan of 5+ years.
🥵 Above 80°F / 26.7°C
This temperature boosts your betta fish’s metabolism. While that sounds like a good thing, it’s actually not. This causes your betta fish to eat, excrete, and move around quicker. All of this will wear out your betta fish and cause it to age quicker. Aging quicker will prevent your betta fish to living up to its full potential lifespan. You can also catch your betta fish burrowing at the bottom of the tank’s gravel to try to cool itself down.
💀 Above 86°F / 30°C
This is way too hot for a betta fish. Expect the betta fish to die after an hour if the temperate remains the same.
I strongly recommend investing in a thermometer and a water heater if necessary. A water heater would be too big for a fish bowl but a great for a tank. A fish bowl is also not the best environment for betta fish either, so hopefully this article convinces you to upgrade your betta fish’s housing 🙂
Without a thermometer
If you do not have a thermometer, here are some ways to tell if your betta fish are in a less than ideal water temperature state.Too cold:
- Eating less or eating nothing
- Decrease movement
- Floating on its side or at the bottom of the tank
- Bigger appetite
- More energy
- Quicker movements
- Burrowing at the bottom of the tank i.e. just trying to find a colder spot in the tank
Changing water temperature
If you are changing the tank’s water temperature, make sure you do this over several days. Betta fish are sensitive to temperature changes, and you wouldn’t want to your betta fish into shock. Likewise, if you’re adding more water into your betta fish’s tank, make sure the water is the same temperature as the current water in the tank. As a side-note, store-bred bettas, as opposed to wild bettas, are more flexible with less than ideal water temperatures. Happy fish keeping!