There is nothing worse than seeing your beloved fish suddenly floating in the aquarium. What a nightmare that is! You checked the cause of death and found out that the water was too warm for them. It’s heartbreaking to see them with no life due to an issue that could have been easily prevented. But don’t fret. You can always start again. And to prevent yourself from repeating the same mistake, it’s time to install an aquarium heater controller.
So, what does this device do? From the name itself, an aquarium heater or temperature controller regulates your fish tank’s temperature. It allows you to set a more accurate and more livable water temperature for the fish than just relying on a water heater. But there are also aquarium heater controllers that automatically turn the heater up or down, depending on the desired temperature you set.
Be careful with handling the aquarium heater controller. It should not be installed inside the fish tank. While the water heater is placed into the water, the controller is outside the aquarium to give you access to control the heater. If the heater malfunctions and makes the water too hot, it automatically stops working. The water temperature can decrease, but that’s much better than keeping the water too warm for the fish.
Cheap & Good | Our Favorite | Customers Choice | |
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Product | WILLHI WH1436A 10A Temperature Controller | Inkbird 1200 Watts Digital Temperature Controller | Hygger 500W 300W Aquarium Heater for Fresh-Water Salt-Water |
Temperature Range | 58-230 °F | 40.0~212 °F | 61-90 °F |
Power Supply | 110V, NEMA 5-15 AC Plug | AC 100-240V, US Double Socket | AC 110-120V, Outlet Socket, Three Pin Plug |
Max Load | 10A, 110V, 1100W | 10A, 100-240V, 2200W | 110-120V, 500W |
Our Rating | |||
Other Benefits of Aquarium Heater Controllers
Aside from regulating the water temperature, an aquarium heater controller helps in ensuring a healthy environment for the fish. If you’re a passionate aquarist, you will know that some fish species thrive on a specific water temperature.
To keep the temperature at bay, a temperature controller is definitely a necessity. Yes, a heater can adjust the temperature, but a heater controller will keep the water temperature stable for the aquatic residents.
In addition to that, many aquarium heater controllers feature a built-in audible alarm. It makes a sound if the water temperature gets too warm or too cold. It simply means that you don’t need to monitor the water temperature from time to time.
What does an Aquarium Heater Controller do?
Basically, an aquarium heater controller regulates the water temperature in the fish tank. It automatically adjusts the temperature according to the value you have set.
First, you need to set up or assemble the device, then install it in the aquarium. Once everything is installed, set the desired temperature using the controller. Second, place the probe into the water and allow it to read the temperature of the water. If the controller shows that the temperature is less than the set temperature, it turns on the heater. As soon as it reaches the right temperature, it turns off the heater automatically.
That’s what a heater controller how and how easy it works.
When do I need a Aquarium Heater Controller?
While an aquarium heater controller is not an expensive device, it’s a good investment if you’re serious about being an aquarist. Even if you’re just setting up an aquarium as a hobby, it will be helpful to install a heater controller. But when do you need an aquarium heater controller? Is it really necessary to have one?
If you want to make sure that the water temperature in the tank is optimal for the fish, you need a heater or temperature controller for that. You can’t solely rely on an aquarium heater because it can stop working without giving you a heads-up. If the heater shuts off, you might see the aquarium inhabitants too uncomfortable. But with the controller, you can easily regulate the water temperature, plus, you can extend the heater’s functionality.
You will also need an aquarium heater controller if you live in a place where the weather changes all year. You can always turn off the heater if the weather is cold. If you don’t give extra attention to the water temperature, you’ll lose the life inside the fish tank. You never want that to happen, so installing a temperature controller is a must-have. A passionate aquarist has to do everything to keep everything in the aquarium in top shape.
What are the Parts of an Aquarium Heater Controller?
An aquarium heater controller has three main parts: the controller, socket, and the temperature sensor probe.
Controller
An aquarium heater controller will not be what it is if it doesn’t have a controller. It’s an important part of the device since that’s what you use to set the temperature. It usually has an LCD or LED display where you can see the values of the temperatures. It also shows the current status of the aquarium.
Socket
Apparently, a heater controller is an electrical device. It won’t work if you don’t plug it in a power supply. The heater won’t work either if the device has no socket. On that note, a socket is another significant part of a temperature controller. Always make sure that your chosen unit has a socket.
Temperature Sensor Probe
The third component of an aquarium heater controller is the temperature sensor probe. It’s the part that you place inside the fish tank to tell you about the water temperature. If you have a saltwater aquarium, remember to purchase a saltwater sensor probe. Typical probes will be corroded if they are submerged into saltwater.
The Best Aquarium Heater Controllers in 2023
Speaking of reviews, you’ll get to know five of the best aquarium heater controllers on the market. We know that it can be overwhelming to choose from thousands of options. So, we have sorted them out for you to make the selection easier.
1st Inkbird 1200 Watts Digital Temperature Controller
Specifications
- Power Supply: AC 100-240V, US Double Socket
- Temperature Range: -40.0~212 °F
- Max Load: 10A, 100-240V, 2200W
This is a random list, but the Inkbird 1200 Watts Digital Temperature Controller is first on the list. It’s a sophisticated device with advanced features, including a free app that sends notifications of all exception cases to your phone. It has a WiFi temperature controller with two relays, allowing you to turn off the device, especially during emergencies. It also features a continuous heating alarm system, which can be set from one to 72 hours. The controller alerts you when the water doesn’t reach the set temperature at a given time.
Pros
- digital controller
- easy to use, no set-up needed
- waterproof sensor
- built-in thermostat
- has dual temperature probes
Cons
- shuts down WiFi system due to many error requests
- annoying alarm sounds
2nd Hygger 500W 300W Aquarium Heater for Fresh-Water Salt-Water
Specifications
- Power Supply: AC 110-120V, Outlet Socket, Three Pin Plug
- Temperature Range: 61-90 °F
- Max Load: 110-120V, 500W
Next on the list is the Hygger 500W 300W Aquarium Heater, an excellent choice for freshwater and saltwater fish tanks. It costs almost $70, but you get more than the price you pay. One of its best features is that you can submerge the heater in the water. It automatically stops heating when the desired temperature is reached and restarts when the water cools down. It has an LED display, and you can conveniently adjust the temperature by pressing the buttons.
Pros
- can be submerged into water
- straightforward installation and usage
- LED display
- automatic on and off
- good for freshwater and saltwater aquariums
- has heating indicator light
Cons
- only shows temperatures in Fahrenheit
- not too cheap
3rd BN-LINK Digital Heat Mat Thermostat Controller
Specifications
- Power Supply: AC 120V, US Socket
- Temperature Range: 32-140 °F
- Max Load: 8.3A, 120V, 1000W
If you want a budget-friendly heater controller, look no further than the BN-LINK Digital Heat Mat Thermostat Controller. It has an easy setup and a three-button interface to set the temperature. It features a digital display that shows temperatures in both Celsius and Fahrenheit. It also has power indicator lights to help you see the display even in the darkness. Its rugged construction makes the unit durable and easy to handle. Best of all, the BN-LINK Digital Heat Mat Thermostat Controller can be used for other purposes such as fermentation, rooting, brewing, and seedling germination, to name a few.
Pros
- budget-friendly
- LED display
- shows values in both Celsius and Fahrenheit
- easy assembly, rugged construction
- versatile, can be used for other purposes
Cons
- can’t be submerged into water
- no automatic adjustments
4th WILLHI WH1436A 10A Temperature Controller
Specifications
- Power Supply: 110V, NEMA 5-15 AC Plug
- Temperature Range: 58-230 °F
- Max Load: 10A, 110V, 1100W
With colors white and blue, the WILLHI WH1436A 10A Temperature Controller looks so clean and pristine. But it’s more than its looks. This heater controller has both heating and cooling modes. You can switch between modes conveniently by pressing the right buttons on the controller. It automatically turns off when it reaches the set water temperature. In addition to that, the screen shows temperature values in Celsius and Fahrenheit. And like the third model, the WILLHI WH1436A 10A Temperature Controller has various applications. You can use it for incubation, home brewing, seedling germination, rooting, and fermentation, among others.
Pros
- affordable unit, simple yet outstanding design
- easy to program
- shows values in Celsius and Fahrenheit
- automatic temperature adjustments
- convenient switching of modes
- doesn’t need WiFi to function
Cons
- doesn’t work so well when cooling down
- no alarm sounds
5th Finnex Temperature Controller Digital Heater
Specifications
- Power Supply: AC Plug
- Temperature Range: 67-93 °F
- Max Load: 800W
Pros
- easy to use, simple programming
- can display temperatures in Celsius and Fahrenheit
- has hi and low alerts
- has audible alarms
- adjustable temperatures
Cons
- only comes with the controller
- not calibrated sensor probes
- doesn’t have a wide temperature range
How do I Choose the Best Aquarium Heater Controller?
You already know what an aquarium heater controller is and when to get one. The next thing to know is what to look for in a high-quality heater controller. Now, that is a tricky one, considering that there are many options to choose from. With that said, what do you look for in an excellent aquarium heater controller? Here are four of the most common things you need to check in a heater controller.
Heater Wattage
The first thing you need to look for in an aquarium heater controller is the wattage rating. It’s usually printed on the package or the device’s manual. As much as possible, choose a controller with a higher capacity than what you need. Forcing the device to go over its limited power can result in overheating and malfunctioning. For example, your water heater is at 800 watts. It is advisable to choose a heater controller with a wattage rating of 1000 or higher.
Freshwater or Saltwater Tank
Does your fish tank have freshwater or saltwater? This factor affects your choice of heater controllers. You can use waterproof temperature probes for freshwater aquariums. But it’s a different story if you have a saltwater fish tank. You can’t use the same temperature probe because saltwater corrodes most metals. However, there are probes specifically designed for saltwater aquariums. You have to choose that if your inhabitants thrive in saltwater.
Heating & Cooling Temperature Range
You also need to consider the temperature range of the controller. Weather changes from time to time, and sometimes, it can get too warm or too cold. To make sure that the water temperature gets adjusted to different environment temperatures, go for a controller with a temperature range. Many devices feature a temp range of -58 to 210 °F, but there are also -30 to 220 °F. Select the one that can cover the temperature range in your area.
Price
And of course, think about the price. As previously mentioned, aquarium heater controllers aren’t really that expensive. They can go as low as $18 to as high as $90, depending on the specifications and features. If you want something sophisticated and advanced, then buy the most expensive option. But there are also high-quality devices with affordable prices. You just need to read legit reviews to know if the cheaper aquarium heater controllers are worth the purchase.
