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If you recently purchased some new Tetras you may be asking a few of the following questions:

  1. Do Tetra Fish Need a Heater?
  2. Can Tetras Survive Without A Heater?
  3. What Is The Ideal Temperature For Tetras?

Luckily we will answer all these questions below and share a few tips to ensure the temperature is set just right for all your Tetras.

Tetra fish are pretty popular in the fishkeeping community, mainly because of their wide range of vibrant colors, their active nature, and the fact that they’re very social swimmers.

As a result, many aquarists choose these tropical fish when they’re first starting an aquarium or looking to expand their current tank.

Like every other type of pet fish, tetras have a set of requirements that you should provide if you want to see them healthy and happy. While a filter and an air pump may be obvious things to include in your tank, other aquarium equipment can be a bit confusing as to whether or not tetras really need them.

Today, we’re discussing one of these pieces of equipment as we answer the question:

Do tetra fish need a heater?

That’s right, aquarium heaters aren’t always necessary for fish to thrive, but is this the case for tetra fish? Well, continue reading to find out!

We’ll also be taking a closer look at the proper water temperature conditions for taking care of tetra fish, the best heaters you can use in your aquarium, the importance of circulation, as well as ways you can maintain consistent water temperature.

Let’s dive in!

My Top Three Heaters For Tetras

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Do Tetra Fish Need a Heater?

Being both tropical and cold-blooded, tetras rely almost completely on water temperature to ensure proper metabolism. Generally speaking, tetra fish thrive in water temperatures ranging between 75 to 78 degrees Fahrenheit. This is also important for breeding.

Consequently, you’ll need to install a heater in your aquarium to produce and maintain such temperatures throughout the day.

Outside of this temperature range, tetra fish will be placed under stress as their immune system becomes suppressed the lower the temperature is. This will put your fish at a high risk of developing diseases and bacterial infections.

Neon tetras, for example, are already prone to many illnesses (ich, columnaris, and neon tetra disease), so tempting fate isn’t a smart move here.

Putting aside the whole immunity and disease issues, can tetra fish live without a heater?

Well, in theory, they can live – just not very healthily. If the room temperature where you’re keeping your aquarium is about 78 or 80 degrees Fahrenheit, then you can probably get away without a heater.

But if the room temperature is lower than 75 degrees Fahrenheit, a heater becomes a must for keeping your tetra fish healthy.

Can Tetras Survive Without A Heater?

All that aside this video from Aquarium Co-Op has a different opinion and to be honest Cory is someone who I would trust he’s been in the game for a very long time.

Heaters – Reaching Optimal Temperature

The purpose of a heater in any aquarium is to raise the temperature of the water inside until it reaches the ideal level according to the type of fish you’re housing. Installing a heater ensures that the tank doesn’t get too cool while maintaining a steady temperature during the course of the day.

As a rule of thumb, a good aquarium heater will provide 3-5 watts for every gallon in the tank. So if you own a 10-gallon tank, it’ll need a 30-50 watt heater.

If you’re looking for a reliable heater for your tetra fish aquarium, then we recommend the Tetra HT Submersible Aquarium Heater. While the Ehiem is my top pick the Tetra HT is simple to use and suits tank sizes ranging from 2 to 55 gallons. It has an indicator that lights red during heating and green when the target temperature has been reached.

This heater also comes with a built-in thermostat to automatically maintain the water temperature at 78 degrees Fahrenheit – the optimal temperature for tetra fish. Additionally, you can install this fully submersible heater horizontally or vertically with a small footprint for easy concealing.

One thing you should pay attention to in any heater is the water level it demands. You want to keep the water in the tank above the indicated mark so the heater operates properly. If the water level falls too low, the heater will work extra hard to raise the temperature, which makes it susceptible to damage.

Thermostats – Monitoring the Temperature

The thermostat triggers the heater to work depending on the water temperature, so it’s rather crucial to the thermal condition of your aquarium. If your thermostat fails, the heater will get stuck either on or off, leaving your aquarium very dangerous to tetra fish as if it didn’t have one at all.

Unfortunately, thermostats have a bad reputation when it comes to durability, so you should invest in a high-quality heater to make sure it has an equally reliable built-in thermostat.

Even then, you should have another way to check the tank’s temperature besides the heater’s thermostat because it doesn’t provide an entirely accurate reading. In this sense, the thermostat can only give an idea of the temperature the heater is trying to achieve.

To solve this issue, you should use an aquarium thermometer that’s both affordable and reliable. The Marina Floating Thermometer is an excellent choice if you’re looking for a cheap fix. It even comes with suction cups for secure mounting.

However, if you need a digital thermometer, then we recommend the Zacro LCD Digital Aquarium Thermometer as it shows that temperature clearly in Celsius or Fahrenheit reading.

Circulation – Keeping It Consistent Across the Tank

An aquarium heater can’t do a proper job without good water circulation from your filter. Such circulation ensures that the water temperature is the same across different parts of the aquarium.

Bubblers, filters, and powerheads are a great way to ensure the water in your aquarium is moving around and circulating.

Temperature Change – Avoiding Sudden Shifting in Temperature

In addition to maintaining consistent water temperature across the aquarium, you should also avoid sudden changes in temperature to prevent harming your tetra fish.

So, make sure to always float the bag of your new tetras on the surface of the aquarium until the water temperature inside the tank is the same as that in the tank.

If the power goes out or the heater breaks down, be sure to cover the tank with a towel or blanket to trap in the heat and add warm water as you see fit.

Wrap Up

So, do tetra fish need a heater? Well, if you want them to be healthy and thriving, then yes. Not only should you maintain the water temperature between 75 and 78 degrees Fahrenheit, but you should also make sure the water temperature is consistent in all parts of your aquarium.

Learn More About Tetras

What's The Ideal Temperature For Tetras Do You Need A Heater