How cold is water with a betta fish in it if just sitting at room temperature no heaters or anything?

It's impossible to give an exact temperature for the water with a betta fish in it at room temperature. Here's why:

* Room temperature varies greatly: "Room temperature" can be anywhere from 68°F (20°C) to 77°F (25°C) or even higher depending on the location, time of year, and the specific room's climate control.

* Betta fish prefer warmer water: Betta fish thrive in water temperatures between 78°F (26°C) and 82°F (28°C).

* Water temperature fluctuates: Water temperature can change depending on the time of day and even the weather outside if your tank is in a room with windows.

Without a heater, it's highly unlikely that your betta's water will stay within their ideal temperature range. This can lead to health problems and even death.

Here's what you need to do:

* Invest in a heater: A reliable heater is essential for betta fish.

* Get a thermometer: Monitor the water temperature regularly to ensure it stays within the recommended range.

Remember: Betta fish are tropical and need warm water to survive. Don't rely on room temperature alone.