In most circumstances, Bettas do need a heater for longevity. So when should they and shouldn’t they?
One thing about this hobby is that so much information is simply parroted until so many people are saying it, that it must be true. Disagreeing with the majority can cause a lot of reactionary drama. But the truth is the inside of a typical house is actually not “cold” and often is plenty warm enough for various tropical fish, so needing an aquarium heater is also circumstantial.
Betta fish come from the shallow, warm water of Southeast Asia. They do well with a water temperature between 72-82°F (22-28C). The truest answer is that whether you need an aquarium heater or not largely depends on the temperature of your house, and how often the fish tank experiences temperature fluctuations.
But what about somebody living in a warm climate that doesn’t have air-conditioning and with a stable temperature inside? In this case, if tank water stays in the ideal temperature range this person would likely be fine without a heater.
When do Betta Fish Need Heaters
Simply put, if your home is below 72°F and fluctuates in temperature by more than a couple degrees, an aquarium heater in your Betta tank is a good idea to keep the aquarium water temperature stable and your Bettas warm enough.
In the US most homes have air conditioning. Personally, I like to sleep at about 68°F. However, during the daytime, I set my indoor temperature to 75F. Without a heater stabilizing the temperature of the water, especially in small tanks like a Betta fish tank, it can cause stressful fluctuations. So in my case, I would need to run aquarium heaters in all of my tanks, not just my betta tanks.
But what about somebody living in a warm climate that doesn’t have air-conditioning and the inside room temperature stays fairly stable and warm? In this case, no this person would likely be fine without a heater.
Choosing the Right Adjustable Heater
Heater Size For a Betta Tank
The heater should match the tank size if you want the adjustable heaters dial to properly set and match the water temperature. What I mean by this is technically you can use oversized heaters in a smaller aquarium, but you should adjust the temperature on the dial lower than what you actually want it to be. 3-5 watts per gallon will usually do the trick. So, a 10-gallon tank would need a heater between 30-50 watts.
Heater placement and Maintenance
In a smaller aquarium, the heaters placement is not super important, but in larger aquariums, or more specifically longer ones, you should put it in a place where it can circulate. So, for example, next to the filter inlet or in front of the filter outlet, so that the filter is distributing heat throughout the aquarium.
Benefits Beyond Temperature Control
Bettas are more colorful and healthy looking at the proper temperatures and a lot more active and interactive. If you look at the betta fish in cups at the store, you’ll notice they mostly just lay there. In an appropriately sized Betta aquarium where water temperatures are optimal, Bettas will be much more lively with a better immune system.
Conclusion: Do Bettas Need a Heater
For betta fish owners, you should analyze your situation and the various factors we discussed to decide whether you need a heater or don’t need one. In a small tank, be sure to use the appropriate-sized heat source and a thermometer to monitor the tank temperature.
