Best Aquarium Thermometers

Everything You Should Know about Aquarium Thermometers

If you think that the temperature in your aquarium doesn’t make a difference, you’d better think twice. More often than not, you need to pay attention on a regular basis. Water that is too hot or too cold can lead to unpleasant surprises, harming both the fish and the plants inside your tank.

Even if you can find aquarium thermometers for excellent prices, you still want to pay attention when selecting. Relying on a thermometer that isn’t accurate is just as effective as having none at all.

TOP 7 Best Aquarium Thermometers

   1. Marina Floating Thermometer

When the market gives you reliable and affordable (we mean really affordable!) tools like Marina Floating Thermometer with Suction Cup, you have no excuse for not buying it.

Where to buy Marina Floating Thermometer with Suction Cup? - the current price is $0.98 on Amazon

Truth be told, the popularity of the thermometer speaks volumes, but the price can seal the deal for most. The thermometer is a floating model that comes with good suction cups. It’s easy to read and incredibly accurate, especially considering the price. Moreover, it shows temperature readings in Celsius and Fahrenheit. It includes a safety zone temperature range indicator, that you can use for your tropical fish. The numbers are clear for effortless reading.

The Marina Floating Thermometer is created for floating the water vertically. Should you want to install it on the glass, you can use the rugged suction cups. They attach safe and secure to your aquarium’s wall.

You can use the thermometer for both fresh and saltwater aquariums. It’s very well made and takes the use for a reasonable amount of time. Thanks to its subtle profile, you may easily hide it behind plants.

Let’s take a look at the functional aspects:

  • It has a subtle profile, and it’s accurate
  • It’s easy to read and reliable
  • It’s a floating model but also comes with suction cups
  • It includes safety zone indicator for tropical fish

The cons are minor:

  • It has a strong chemical smell out of the box
  • Some think that the red line is quite thin and not easy to read

Regardless of the small problems, the thermometer is easy to read, to use, and accurate. It definitely doesn’t empty your pockets and can work just fine for many aquariums.

   2. Zacro LCD Digital Aquarium Thermometer

Another affordable thermometer that doesn’t disappoint in terms of precision or performance is Zacro LCD Digital Aquarium Thermometer.

Zacro LCD Digital Aquarium Thermometer - buy it on Amazon for price $6.99

It’s a digital thermometer that is reliable and easy to use. You may submerge the probe in the aquarium for measuring the water temperature. You don’t need to submerge the thermometer; only the probe.

The thermometer features a suction cup that is easy to apply. The LCD screen is clear and significant, ensuring effortless reading. Keep in mind that the thermometer reading has a one-degree deviation.

Since it’s small and compact, both the probe and the thermometer are subtle. You can have the readings in Celsius or Fahrenheit. The temperature range is -50 to +70 C degrees, whereas the operating temperature ranges between -10 to +50C degrees.

The thermometer is powered by one LR44 button cell that lasts for a fair amount of time (four months or so). You can easily attach the unit to the outside of your aquarium with suctions cups while submerging the probe into the tanks.

Let’s give the positive aspects another read:

  • The thermometer is digital and accurate
  • The probe is small and compact
  • It’s easy to attach the thermometer with the suction cup
  • The LCD is large and easy to read

We’re not backing down over some minor shortcomings:

  • Turtles may bite the wire of the probe
  • Check the battery from time to time so that you get accurate readings

All in all, the thermometer is dependable, easy to use and to mount, leaving you plenty of money for buying something else for your fish.

   3. General Tools AQ150 In and Out Aquarium Thermometer

The General Tools AQ150 In and Out Aquarium Thermometer with Waterproof Probe is an in and out aquarium thermometer.

General Tools AQ150 In and Out Aquarium Thermometer with Waterproof Probe - buy it on Amazon for price $19.99

The digital thermometer is capable of measuring temperatures ranging from -58 to 158F degrees. It comes with a minimum and maximum memory and high/low-temperature alarm. The alarm isn’t too loud, but you’re going to hear it nine times out of ten. It’s going to help you maintain the temperature exactly where you want.

The digital thermometer shows the temperature with big numbers, which are easy to read. You can also switch from the ambient/remote sensor temperature, but also from Celsius to Fahrenheit.

It’s an industrial appearance for the thermometer, which comes with a backlight display and comfortable foldaway stand.

The probe comes with a rugged bracket, whereas the digital unit has a strong magnet on the back. The backlight for the display is bright, and the suction cup is flexible yet sturdy. The probe’s cord is a 10ft cord, and the thermometer is a great tool to have for monitoring the water inside the aquarium.

Several aspects caught our attention:

  • It includes minimum and maximum memory
  • It also has a high/low-temperature alarm
  • The suction cup is solid, the magnet is secure, and the probe cord is long
  • It’s reliable and accurate

We’re not utterly amazed by the flaws:

  • The instruction sheet could be more helpful
  • It doesn’t run on AAA batteries but CR2032. They’re not as affordable, but definitely more durable and less prone to leakage

Loaded with great features and only presenting minor flaws, the thermometer is a sure buy on any given day.

   4. Inkbird Digital Aquarium Thermometer for Fish Tank

Specially made for freshwater and marine aquariums, the Inkbird Digital Aquarium Thermometer for Fish Tank is loaded with features for any devoted aquarist.

Inkbird Digital Aquarium Thermometer for Fish Tank - buy it on Amazon for price $35.98

The LCD digital display is big and easy to read. It comes with built-in display light, whereas the magnet on the back eases out the mount.

The versatility of the thermometer is excellent, and you can use it as a household Temp&RH monitor after unplugging the external probe. It displays Celsius and Fahrenheit readings. It uses 2x AAA batteries, which are very easy to find in stores.

The external probe is entirely submersible. The list of functions includes alarm and data history view. The data record interval is easy to adjust for better customization.

On top of everything else, the thermometer comes with an app that supports several languages. You can quickly and freely monitor the temp and humidity from Android or iOS gadgets.

Let’s check the useful features once more:

  • It provides readings for temp and humidity
  • You can use it for aquarium or household purposes
  • It comes with iOS and Android App
  • It’s accurate and comes with many functions

There aren’t many things to complain about:

  • It needs calibration
  • It’s not the cheapest thermometer

Nevertheless, the thermometer is an excellent tool for the modern aquarist that is all about the apps and controlling from a distance everything, aquarium included.

   5. Lifegard Aquatics Digital Temp Alert

There are many good things to note about Lifegard Aquatics Digital Temp Alert, with accuracy and effortless reading being the most significant ones.

Lifegard Aquatics Digital Temp Alert - buy it on Amazon for price $42.52

The thermometer comes with a large display so that you can easily read the temp from across the room. Not only that, the thermometer is accurate, but it also comes with Alert function. Should the temperature in the tank be too high or too low, the thermometer will let you know and ring the alarm. You can use 4 Alert features: high temp alert only (probe), low temp alert only (probe), both high and low temp alert only (air/room), and both high and low temp alert only (probe).

You get to find out the temperature inside the tank and the room temperature, which only increases the functionality of the tool.

The plastic probe is robust, and it’s made with plastic. It includes both a cord for hanging and suction cup for attaching. It only adds versatility to the picture.

Unlike other digital thermometers, this one runs on durable and easy to find AAA batteries. The thermometer works for both salt and freshwater. It’s a solid choice for aquariums, greenhouses, and terrariums.

We’ve shortened the pros to the following:

  • It has a large display with both C and F readings
  • It gives temperature for water and room
  • It includes 4 Alarm features
  • It runs on AAA batteries

The pet peeves are nothing to worry about:

  • The probe could be of better quality
  • Some doubt its durability

However, the thermometer is versatile, dependable, and accurate. It comes with Alert functions, which only makes the maintenance of your aquarium a lot easier to address.

   6. Atlantis Aquatics 3 in 1 Aquarium Meter

Any dedicated fish lover is patient enough for calibrating an accurate tool like Atlantis Aquatics 3 in 1 Aquarium Meter [Temp, pH, TDS].

Atlantis Aquatics 3 in 1 Aquarium Meter [Temp, pH, TDS] - buy it on Amazon for price $79.99

For just one price, you get a tool that tells you the temperature, pH, and TDS (Total Dissolved Solids) in your aquarium. It’s designed for tanks under 1″ thick once you removed the screw,

The thermometer is accurate and displays reading in both Celsius and Fahrenheit, with just a press of a button. You can quickly check the temperature for providing the best health conditions in the tank. The device is safe to use for freshwater and saltwater aquariums.

The pH meter will give a reading to the tenth decimal so that you know that your coral, aquatic plants, and fish are in ideal water conditions. Keep in mind that you may have to calibrate the pH every six months. The gadget comes with the powders you need for calibration. You need

As for the TDS meter, it provides a sum for all the dissolved solids inside the tank. It includes chlorine, nitrates, GH, KH, and nitrites. If the TDS is high, you should solve the problem and have an aquarium test strip.

The readings are accurate, and the tool is easy to use.

Let’s give the right things another look:

  • You get accurate readings on temperature, pH, and TDS inside the aquarium
  • The thermometer is easy to read and displays both Celsius and Fahrenheit readings
  • It’s easy to use
  • It’s reliable and has a good build

The negative aspects don’t undermine its overall value:

  • Some may find the calibration challenging to make
  • Attaching it isn’t as easy as expected

Even if the tool isn’t all roses and rainbows, it’s still a precise and reliable tool to use for aquarium.

   7. Teffo Aquarium Temperature

With Wi-Fi gadgets being all the rage for some time now, we can only understand why aquarists look for a thermometer that offers a lot more than the accurate temp in your tank. Teffo Aquarium Temperature Controller w/Magnetic Sensor Wi-Fi Thermometer is a gadget helping you monitor, check, and care for your aquarium on a   new level. You can use it for managing and keep the aquarium clean more comfortable than ever before.

Teffo Aquarium Temperature Controller w/Magnetic Sensor Wi-Fi Thermometer - buy it on Amazon for price Click to see

The gadget includes a constant temperature system with two stages. It comes with a six-point temp controller so that you can control the heater and the cooler at the same time. thanks to the Control Manage and Remote monitor function you can check your aquarium at any point, no matter where you are. You only need 3G/4G/Wi-Fi smartphones to do it.

The list of functions includes an Automation Schedule and scenario according to your needs; they are operated almost instantly. A Mobile Alert can be also sent once the cloud identifies that the data is no longer within your setup. You only need to click the “Auto” button so that your aquarium gets back to work.

The magnetic temperature probe is easy to attach to the tank, as long as the thickness ranges from 5mm to 15mm.

Teffo is a Wi-Fi smart controller that you can use for controlling your aquarium from a distance. It can sustain more than ten different devices, allowing the effortless inclusion of an existing aquarium to the ecosystem. The system is easily managed through the cloud, thanks to the controlling and monitoring functions.

With Teffo, you’re not only gaining a thermometer. You receive a tool that makes aquarium maintenance a breeze.

Let’s have another look at the positive aspects:

  • It’s a Wi-Fi smart controller for managing the aquarium
  • It helps you monitor and control the aquarium from a distance
  • You can connect the cooler and heater for obtaining a constant temperature
  • It includes several functions and even sends notifications about any problems

The shortcomings shouldn’t stress you out:

  • It may difficult to connect it if you have a mesh connection
  • Some think that it’s not always reliable

Stay focused on the right parts as they outweigh the bads by far. It may seem pricey, but Teffo is an excellent tool for any aquarium owner living in the 21st century.

How do you know which aquarium thermometer is good for your aquarium?

It goes without saying that only feeding your fish or cleaning the tank isn’t going to be enough for keeping them healthy and happy. Having the right temperature in the aquarium is also essential, and you don’t want to find out the hard way. Heating systems for aquariums are one way to make sure that the water is never too hot or too cold. However, it’s the thermometer that always tells you the temp inside the aquarium.

Not all aquarium thermometers were created equal, and the market gives you plenty of options to choose from.

Here are some aspects to consider when selecting the thermometer for your aquarium:

  • Thermometer type

There are three main kinds of aquarium thermometers:

  • Liquid-filled- they resemble the traditional mercury bulb thermometers. However, they’re filled with a substance that is less dangerous than mercury. Some models sit inside the aquariums, whereas others can float/sink/come with a suction cup.
  • Digital thermometers- they feature a probe placed inside the aquarium, and the display unit is attached on the outside. Some models are different, though. Modern models come with impressive features and alarms.
  • Adhesive strip thermometers- they present flexibility and the thin profile allows you to stick on the outside of the tank, providing an approximate reading.
  • Precision

it’s quite common for aquarium thermometers to present the degree of precision with which they record temperatures. A good quality thermometer will have a +/-2F degree accuracy. You don’t want a thermometer with low degree of accuracy, especially if the fish need very specific temperatures. An inaccurate thermometer is useless, so look for a well-calibrated model. It will help you know the temperature inside the aquarium.

  • Ease of reading

Naturally, the digital thermometers that feature a large LCD display are effortless to read, especially when you don’t deal with any eyesight problems. Reading a liquid-filled model may be challenging at times. however, you should still be able to read the temp to within a degree or two. In the case of adhesive strip models, they feature a system of different colors for displaying the precise temperature. Make sure you read the instructions to find out what do the colors mean.

  • Power options

It’s evident that digital thermometers run on batteries, so make sure you have plenty inside your home. Some models require AAA batteries, which are easy to find and cheap. Others may require less common batteries (CR2032 is one) that are, on the other hand, more durable and less prone to corrosion. Both adhesive strip and liquid-filled thermometers don’t need any batteries for operating. It’s not a bad idea to have one as a backup when the battery on the digital thermometer dies.

  • Lifespan

Expect to pay the extra buck if you want an aquarium thermometer that lasts for a long time. Liquid-filled models have to be rugged and tough, since they may harm the fish if they shatter inside the aquarium.

FAQs on aquarium thermometers

Q: What’s the best way to use a digital aquarium thermometer?

A: You want to use a thermometer for measuring the temp inside the aquarium. Some models let you check the temperature regularly and even alert you if the temperature gets too high/too low. For the huge aquariums, it’s better to use not one, but several thermometers for monitoring various areas of the aquarium. You need to make sure that the display is easy to read so that you may know the temperature instantly.

Q: Is there a special place where to stick-on the thermometer?

A: Stick-on thermometers are very common to use for freshwater aquariums. They’re even included as a feature for an aquarium package. In the case of LCD thermometers, there are some tricks to keep in mind for getting best results. You shouldn’t place the thermometer below ground level, as it may alter the precision of reading. Make sure that the thermometer doesn’t come in contact with direct sunlight nor area close to a heating/cooling vent. You shouldn’t place an aquarium in such areas anyway. Also, remember that a thermometer gives best reading when you view it straight on, as it’s set correctly. If you have to twist your body for reading it, it means it’s not the best place for the thermometer.

Q: Are digital aquarium thermometers more accurate than others?

A: Any thermometer that is appropriately calibrated should be more precise than any model that isn’t.  It’s very true, especially if it can provide the water temperature to one decimal place. Cheap digital thermometers can lack precision, but it doesn’t mean that all pricey models are highly accurate either.

Q: Is there an ideal temperature for water inside an aquarium?

A: The proper temperature inside the aquarium depends on the type of fish you have. Many tropical fish need water temperatures between 76 and 80F degrees, but some tropical species may feel better in somewhat higher/lower temperatures. For instance, goldfish like a lot lower temperatures, with single-tailed goldfish liking even more moderate temperatures.

Q: Does the room temperature impacts the temperature in the aquarium in any way?

A: You don’t want to place the aquarium in a   chiller room. When you don’t have another option, it’s better that you also install a large heater in the aquarium. Any aquarium that doesn’t have a heater and it’s placed in a cold room is going to be affected by the room temperatures. Therefore, you should always take into consideration the room’s temperature when worrying about the aquarium temperature.

Scroll to Top