Do Neon Tetras Need a Heater? Everything You Need to Know

Neon tetras require a heater in the tank. In fact, they’re unlikely to survive without a heater, as the temperature is crucial for the fish’s health. Neon tetras require a temperature between 75 to 80° F, and any temperature below or above that level will put them at risk.

Do you want to find out more? In today’s article, we’ll tell you everything you need to know about neon tetras’ need for a heater. Let’s dive in.

Do Neon Tetras Need a Heater?

Simply put, neon tetras need a heater to survive unless you can maintain a higher temperature year round.

The reason is that neon tetras are freshwater fish native to the Amazon basin. This means neon tetras require a temperature between 75 to 80° F.

In most parts of the world, maintaining a water temperature of 75° F is not really possible in the winter. Hence the need for a heater.

That’s why your neon tetras need a heater to keep a constant habitat.

Neon Tetra Close Up

How to Pick the Right Heater for the Neon Tetras’ Tank

Heaters, as the name suggests, can maintain the temperature of the water in your tank at a certain point. So, are all heaters the same?

Heaters come in different wattages. So, you’ll need to choose a heater with a high enough wattage. This way, the heater can sufficiently heat the tank without an overload, or worse, not reaching the desired temperature.

The general rule of thumb is to get a 2.5 to 5 W heater for every gallon of water in your tank. Therefore, it’s crucial that you measure the size of your tank before buying a heater.

Additionally, you need an aquarium thermometer to keep track of the water temperature. Always act quickly if you notice that the temperature isn’t suitable for your neon tetras.

The Most Suitable Temperature for Neon Tetras

Neon tetras love to be in a temperature range between 75 and 80 °F. Many fish breeders suggest that the temperature can go above this range. However, there’s no need to disturb the ecosystem and make the neon tetras feel uncomfortable.

Neon Tetras and Cold Water

In order for your neon tetras to survive, it’s crucial that the temperature not fall under 72° F. That’s because your neon tetras can’t tolerate being in a temperature lower than 72° F, which can be fatal to them.

Changes in Appetite

The low temperature can cause many problems for your fish. First, they’ll have a decreased appetite. Additionally, they’ll be having trouble with digestion and breathing. Accordingly, you’ll notice that your neon tetras become inactive and sluggish.

Fin Rot and Neon Tetra

Your neon tetras might also be prone to many diseases like fin rot and neon tetra disease.

Fin rot is a fatal disease that’s caused by bacteria and fungi. It infects the neon tetra fins, leading them to change colors and eventually fall off. Also, neon tetra disease is a fatal disease that spreads fast between neon tetras, and it’s really hard to cure.

Fish Parasites

Moreover, fish ICH, which is scientifically known as Ichthyophthirius multifiliis, is a common fish parasite that causes white spots on neon tetras gills and the body. It’s also a life-threatening disease.

These diseases will take advantage of your fish’s bad state and weak immune system to attack. So, to avoid all these risks, you need to keep the water temperature above 72 °F.


If the temperature falls below 60 °F, neon tetras will go into shock. This can be a life-ending situation for your fish.

Neon Tetras and Hot Water

Putting your neon tetras in a tank that’s too hot for them is something you definitely don’t want to do. The reason is that neon tetras are cold-blooded, and their gills won’t work properly in hot water.

Moreover, the high temperature can speed up your fish’s activity. This means the neon tetras’ metabolism and breathing rate will be too quick, and they’ll likely die of hyperactivity.

Not only will the neon tetra’s body suffer, but hot water generally has less oxygen. This can lead to your fish dying from suffocation.

Additionally, if you set the heater too high, your neon tetras might be at risk of burning. That’s because neon tetras are incredibly active fish and might get too close to the heater.

Group of Neon Tetras

What to Do if the Heater Breaks Down

If your heater isn’t working properly, especially in extreme weather, it can be life-threatening to your neon tetras. Therefore, it’s best if you keep an extra heater in case of emergencies like that.

If you don’t have a spare heater, there are a few things you can do to help keep the temperature in the desired range until you get a new heater.

  • Cover the top of the aquarium to limit heat loss.
  • If you’re in cold weather, get a thick blanket and cover the entire tank.
  • You can also place household heaters close to the fish tank.
  • In hot weather, turn on the AC and fans to cool off the temperature.
  • If the temperature is getting too high, you can add some unchlorinated ice cubes to the tank.
  • Wrap the filtration system with linen to protect it.

To Conclude

So, do neon tetras need a heater?

The answer is yes! It’s crucial for the health of neon tetras that the temperature remains between 75 and 80 °F.

Otherwise, it can be extremely harmful to your neon tetras. Colder temperatures can cause many diseases to your neon tetras, including fin rot, fish ICH, and neon tetra disease.

On the other hand, in warmer temperatures, your neon tetra will have trouble using its gills. Also, the oxygen levels will decrease, which will lead to suffocation. Therefore, neon tetras require a heater in their tank at all times.