Petting fish seems to be simpler and easier than other animals, sure, but it is not just introducing them to an aquarium and hoping for the best. You need to make sure the environment they are living in is livable and comfortable, which requires you to closely monitor their water parameters, including temperature. If you have tropical fish or any marine life that needs warm water, then you probably need need a heater for your aquarium. But how do you know your aquarium water has the right temperature? That is where an aquarium thermometer plays an ultra important role.

In this article, we will review 8 of the best — most accurate and affordable aquarium thermometers, you can count on them to give you an accurate number and do your part to make sure your fish live happy and healthy.

Marina Floating Thermometer with Suction Cup

Marina’s Floating Thermometer with Suction Cup for Aquariums is a reliable, high-quality floating thermometer. It’s accurate and easy to read and provides temperature readings in both Celsius and Fahrenheit. There’s also a clearly marked safety zone that shows the ideal temperature range for most tropical fish.

The Marina Floating Thermometer works in both freshwater and saltwater tanks and is designed to float in a vertical position. A suction cup is included if you prefer to attach it to the aquarium wall.



Zacro LCD Digital Aquarium Thermometer Fish Tank Water Terrarium Temperature

This is suitable for different water types such as fresh water, tap water, salty water, marine water and etc. You can choose seither Fahrenheit or Celsius according to your need. Displaying temperature measurements within 0.1 degrees! And has a temperature range from -50 to +70 degrees celsius.  What’s more, each thermometer is equipped with a LR44 battery.

This is very easy to read due to it’s large LCD display, which is attached to a submersible probe.  It features a suction cup, so you can attached it to the outside of your tank and monitor with ease. 



HDE Digital Aquarium Thermometer Fish Tank Thermostat

This is another nice large LCD display with probe. You’ll find this very easy to read and monitor your tank’s temperature. It’s versatile, offering a temperature range between -50 and +70 degrees Celsius. And it displays precise, 0.1 degree readouts which are accurate to +/- 1 degree. You’re able to use a simple switch to change from Celsius to Fahrenheit.

This comes in pairs, so for as less as $10, you will get two digital thermometers, two probes, and of course, batteries are included!



LCR Hallcrest A-1005 Liquid Crystal Vertical Aquarium Thermometer

If you’re looking for a simple and basic thermometer this could be a great choice for you. Using the easy stick peel and stick design, you mount this vertically on the outside of your tank below the waterline.

Featuring color changing liquid crystals, the numerical display is very easy to read and is fairly accurate.  You can remove and re-position the thermometer. It’s best suited to smaller tanks. Again, I would recommend using this with another more accurate heater.



Zoo Med Digital Thermometer

Keep your pal at the proper temperature for optimum health and wellbeing with the Zoo Med Digital Thermometer. Specially designed to accurately measure the temperature of terrariums and other enclosures, it has an easy to see LCD screen that displays both Fahrenheit and Celsius, with no cumbersome settings or buttons.

It has a remote sensor probe that lets you check the temperature in dry or wet substrates, and can be easily installed inside your enclosure with the convenient suction cups. Thanks to its small design, you can display it anywhere on your tank without obstructing your view of your pal.



Digital Touch Screen Fish Tank Thermometer

This Mini Digital Aquarium Thermometer comes with modern appearance and compact design, easy-to-read clear LCD Screen delivers accurate temperature readings in your Terrarium. It is important for you to own this one to keep your pet fish healthy, happy and active.

It needs no probes or messy wires in water, backside temperature sensor stick on the outside glass of the fish tank prevent water infiltration and electronic oxidation, classic red+black compact design with large crystal touch screen makes it easier to read the temperature far away, stands out among other Fish Tank thermometers.



JW Pet Company Smarttemp Thermometer Aquarium Accessory

The unique design of the JW pet company smarttemp thermometer combines a thermometer with a magnet. The smart temp thermometer goes on the inside of the tank and the magnet goes on the outside to hold the smarttemp firmly in place, no suction cups needed.

The smarttemp also offers a green safe zone which indicates the optimal temperature range. A high-end accuracy- (+/-) 1.5-degree f and the smartTemp has large easy to read numbers. It also offers a standing version, which is weighted and fits securely in gravel, both works great and well enjoyed by many fish owners!



American Thermal Horizontal Aquarium Thermometer

This thermometer is movable on the outside of the tank. An exact temperature sense is likely with this great device. Press the thermometer solidly to keep it in place on either the load line or outer tank surface.

In other words, the device is a stick-on type as agreeing to how it is installed. The construction is very light and compact. It has sensitive color-changing fluid crystals which are good for fishes. Anyone can easily see its enlarge accurate result figures. The device is under a strict laboratory specification about its temperature pointer.