How Do I Know If My Aquarium Heater Is Working

How do I know if my aquarium heater is working – A vastly asked question!

Aquarium heaters are one of the most indispensable accessories of Fishkeeping. A heater keeps the aquarium warm and cozy for the aquatic critters. In cold weather, where room temperature is relatively low, a heater must-have for the fish to survive in the tank. 

On the flip side, a heater can kill your fish if it doesn’t work correctly. Likewise, it can burn the fish; if it malfunctions and does not turn off when it is supposed to. Conversely, suppose it stops working and is unnoticed. In that case, the aquarium temperature may reach below the minimum threshold temperature for the fish. Eventually, it will cause stress to your fish and even may die. 

So a vital piece of equipment like a heater can become a reason for a nightmare if you don’t know if the heater is working or not. Usually, inexperienced fishkeepers face this problem very often, and they get confused about the heater’s functionality. It is easy to blame the manufacturers, but sometimes heater problems arise from a user’s negligence and misunderstanding.

So, you’ve got a fish tank and an aquarium heater? That’s great! But how do I know if my aquarium water heater is working? First, you must know how your equipment operates so that you don’t accidentally make a mistake with potentially fatal consequences. 

Read below as we discuss some critical points about aquarium heaters, which will help keep them working efficiently without any danger or worry on your end.

What Are The Reasons Behind For Heater Isn’t Working:

Faulty Sockets And Power Supply

There are many reasons why your heater may not be working. The first step is determining why the heater isn’t working – it may not be faulty at all! 

Many people assume their heaters are broken when they’re actually just plugged into an outlet with no power running through them. You should check the socket where it plugs in to see if there’s any damage or faulty.

You can test this by connecting another appliance safely and seeing if it turns on as well. If your other devices do turn on, then we know for sure that the wiring is good! If no other devices work with your faulty socket, you should replace it immediately. 

The Indicator Light Is Not Turning On Or Frequently Turning On/Off

Your fish tank heater is key to keeping your aquarium at an appropriate temperature. If the light on it isn’t lit, you’re not getting any heat for your pet fish! All heaters turn themselves on & off automatically to regulate temperatures in order to avoid overheating!

If your aquarium light is on, but the heater and water do not feel warm enough for you, it may be a good idea to replace them. The reason is, if this occurs, it’s likely that there is a loose or broken contact within the aquarium heater. Also, many heaters come with other features like timers or digital displays, making life easier; so, go ahead and invest in something new!

If the light on your fish tank heater is turning off and on quickly, it might be a sign that something is wrong. However, the problem is not the light but the heater. If it’s too large or powerful for your tank, you’ll need to get a more appropriate size and wattage so that it doesn’t cycle on and off quickly. 

The Heater Is Cracked Or Salt Deposits

Unplug the heater and let it chill for some time; after that, remove it from the aquarium. If any breakage or wear is detected on the heating system itself, a replacement should be made before use. 

It’s not uncommon for glass to crack, metal corrodes, or colors change, and the suction cup loses its grip. Suppose you notice any of these changes happening regularly. In that case, it could indicate that your heating elements are starting to wear out over time and need an upgrade. 

In addition, cleaning out mineral deposits or algae build-up will improve performance and lower overheating risks for your pets!

Fault In The Internal Thermostat Of Aquarium Heater

A thermostat is a built-in device of aquarium heater that regulates the temperature of your tank. The heater will automatically adjust its heat output based on what you have preset. And it tracks changes in tank temperatures, turning off when it reaches or exceeds a range you’ve established. 

The thermostat may become faulty; that’s why you should invest in the extra safety net of an additional temperature controller on top of what already exists there! If one fails, the other will hopefully catch up and ensure that everything stays safe and sound for all those living inside. 

You Forget To Unplug The Heater During A Water Change

Don’t forget to unplug the heater during the water change so that the water level doesn’t go below the heater’s position. If it runs dry, there is a high possibility that your heater may not work further. 

Although some high-quality heaters have a built-in protection system to prevent any damage to the heater because of low water level, it’s never a guarantee. 

Proper Placement Of The Heater

The placement of the heater is vital to transmitting heat effectively. When you put your heater in a tank of water, the cold, less dense water rises to the top and pushes the hot, more dense water down. 

This increased water circulation, in turn, speeds up your process. It raises the temperature more quickly so you can have a faster result more efficiently.

To make sure water is heated evenly in your tank, place the heater near circulation points. The heater’s position close to the water filter exit point or near the airstone can help distribute temperature throughout your tank in less time. 

The Heater Is Overstressed Or Not The Right Size Heater

Improper heater selection is one of the main reasons for heater malfunction. When you select an undersized heater, that puts a tremendous load on the heater to raise and maintain the temperature. 

That means your heater has to overwork to reach the desired set point. If it happens, it increases the likelihood of the device failing. Here are some points for determining whether or not you have enough heating power

What are the guidelines for heater selection? The right way is to do some math beforehand. In general, you need 2.5 to 5 watts per gallon of water. However, the heater wattage requirements vary depending on where it is being used, with warmer or tropical weather requiring less power than colder climes. 

So, here the temperature difference between the room and your desired temperature in the tank is the contributing factor while choosing a heater. It would help if you considered the higher temperature difference. Usually, the required tank temperature remains the same; the room temperature varies with climate change. So, take the lowest temperature. 

Multiply the tank water volume with the temperature difference, and you’ll find the heater size you need. For example, suppose if you have a 10-gallon tank, and you need to raise the temperature 10 degrees above the room temperature, you’ll have a 100-watt heater to get the optimum performance. 

Read more:

How Do I know If My Aquarium Heater Is Working?

Most people take their aquarium heaters for granted. That’s a mistake! There are many ways to understand whether the heater is working correctly. It could be using a thermometer, using your hands (old-fashioned), or testing it in another bucket of water before you put it into your tank. 

Use A Thermometer

How Do I know If My Aquarium Heater Is Working - Thermometer

The best way to tell if your aquarium heater is working accurately and how it will affect the fish in your tank is by using a thermometer. Once you set the heater in the tank, please turn it on and introduce a thermometer. 

Notably, it will take some time for your fish tank’s water to heat up – so get ready by noting down its base temperature then checking in after 24-48 hours have passed.

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The water in my ten-gallon aquarium took around twenty-four hours to heat up properly. Larger tanks may need more time before reaching their desired temperatures. 

Observing the temperature fluctuations using a thermometer is an excellent way to understand if the heater provides the desired output. 

Your heater might be going out if the temperature inside your tank is fluctuating too much. Always use multiple heaters when required, especially for large tanks. This helps to prevent an overworked heating element from dying out soon. 

Bucket Test

How Do I know If My Aquarium Heater Is Working - Bucket method

If you are in a rush to see the results of your tests, there is an alternative workaround. 

To test an aquarium heating device, get about two and a half gallons worth of water- enough to submerge the device fully. Measure the water temperature before you put the heater body into the water; about an hour later, check again for any temperature change! 

Let’s see if it had increased from when you measured initially. Remember that you should use a glass container for this measurement like you might use at home or cooking. 

If the temperature increases and maintains the preset point, the heater is absolutely working fine. If it’s not, there might be issues with the heater. For example, it might have been cracked or broken during transportation.

The bucket method is only possible if you use a partially submersible or submersible heater. It’s not an option for in-line heaters or substrate heaters. 

Using Your Hands

How Do I know If My Aquarium Heater Is Working - with hand

You might be wondering how to know if your heater is working without a thermometer. Fortunately, there’s an easy way to use only your hands! 

Ensure your hand is steady as you glide it over the device because if you accidentally touch the exterior of the heater with your fingers, there will be nothing but regret for you. 

As with all electrical equipment, there is always the likelihood of electricity leakage. So even if it’s fully submersible, you never know what might happen, although the risk seems low. 

Unplug your heater before putting your hands in water to avoid any chance of shock injury! Then, check throughout the tank to check if heat is being dissipated evenly.

Tips For Installing The Heater 

The heater is a great investment for your fish tank because it will keep the water at an optimum level of warmth. However, you should follow these steps when installing the heater to ensure its longevity:

  1. Let the new heater acclimate – Set it up properly and let it chill out for about 1 hour before plugging or setting up temperature controls on them. This gives time to acclimatize because any sudden temperature changes could crack the heater glass prematurely.
  2. Check all wires – You don’t want anything impeding against other things as they can short circuit if something goes wrong.
  3. Keep cords away from sharp objects like stones. 
  4. Use thermometers! They may cost more but are much safer than just guesswork.

How To Make The Aquarium Heater More Reliable And Failsafe?

Heaters are one of the most essential pieces to your fish tank, but they’re also highly vulnerable. A heater malfunction may destroy years worth of hard work on building up an aquarium with beautiful decorations and live Rock! So how do you make this device more reliable? You can increase the reliability of your aquarium heater in two different ways: 

How To Make The Aquarium Heater Failsafe

#1: Run two small size heaters instead of a single large one

I recommend purchasing two smaller heaters for any tank instead of a single large device. For example, suppose you need 100-watt heaters in your aquarium. In that case, I suggest using two 50 watt heaters to avoid failure and malfunction the day!

In that way, the heating load will be distributed. When you have two smaller heaters, even if one fails, it will not be able to cook your tank inhabitants because it’s not powerful enough. One heater failure may raise the temperature, though, but not to a deadly level. 

#2: Use a separate temperature controller unit

Another option is buying a separate controller, which will be independent of the heater’s central controller. The fail-safe design of the temperature controller ensures that if one fails, then it will be caught up by another. Thus two failed controllers at a time are pretty unlikely!

If you’re extra cautious, I recommend buying two smaller heaters and also an extra controller. With these precautions, the likelihood of the tank crushing because your heater failed is almost zero!

Some Reliable Heaters to Look for

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Fish tank heaters are a necessity for any aquarium. They keep the water at an appropriate temperature to sustain life. Without them, there will be some severe consequences for all the delicate inhabitants living in it.

It’s important to know if your aquarium heater is working to keep the temperature stable for your fish. This article has outlined some signs that indicate faulty or old aquarium heaters and what you should do about them. 

The best way to know if your aquarium heater is working is by paying attention to the water temperature and checking for any evidence of leaks or other issues with the unit. If there are no problems with either, you can be confident in knowing that everything is running smoothly.

If you’re still unsure if your aquarium heater is working or not,post-purchase customer service can be helpful!

Sujit Modak

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