How cold does it have to be for a betta fish die?

Here's what happens when temperatures drop:

* Below 70°F (21°C): Betta fish become sluggish, their metabolism slows down, and they are more susceptible to diseases.

* Below 65°F (18°C): Betta fish are at risk of hypothermia, which can be fatal.

It's important to note:

* There is no specific temperature at which bettas will definitely die. Each fish has its own tolerance, and other factors like the fish's health and acclimation to the temperature can play a role.

* Sudden drops in temperature are much more dangerous than gradual changes.

To keep your betta fish safe:

* Maintain a consistent temperature in their tank.

* Use a heater to keep the water warm enough.

* Avoid placing the tank near drafts or cold windows.

* Monitor the water temperature regularly.

If you notice your betta fish becoming lethargic or showing other signs of illness, it's important to take action immediately.