* Filters: Filters help to remove waste and debris from the water, and they also help to keep the water oxygenated. It's important to have a filter that is rated for the size of your aquarium.
* Heaters: Heaters help to keep the water at a constant temperature. Betta fish prefer water between 75-80 degrees Fahrenheit. A heater that is preset to the desired temperature is recommended, as betta fish are susceptible to temperature changes and can easily become stressed or ill if the water is too cold or too hot.
Without a filter and heater, your betta fish could develop health problems and die.