The Best Fish Tank Thermometer

Having a good fish tank thermometer is very important. It could be the difference between life and death for your fish!


A couple of years ago, when I didn’t have a fish tank thermometer, I remember walking past my fish tank and wondering why they were all swimming so slowly. In passing, I thought, ‘why aren’t my fish swimming much?’ But I didn’t investigate any further.


It wasn’t until the next day when one of my favorite fish, Little Moe with the Gimpy Fin, was floating upside down that I took a closer look. I found out the heater in my tank had come unplugged! Little Moe, who had a birth deformity leaving him with a crippled tail, and who was a weak, poorly fish, was first to go. He succumbed to the cold.


This could have been prevented if I had a fish tank thermometer. It would have immediately caught my eye that the water temperature had dropped dramatically, and Little Moe would still be with us.


Don’t let what happened to Little Moe happen to your favorite fish – get the best fish tank thermometer today!


best fish tank thermometer


The Best Fish Tank Thermometer


I’ve selected three of the best thermometers for you to consider. These are all cheap fish tank thermometers, but they don’t need to be expensive to do the job! It is good to double check them from time to time to make sure they are working correctly, or in the case of a digital thermometer, to make sure the battery isn’t flat.


Let’s take a look at what we’ve got.


1. Zacro LCD Digital Aquarium Thermometer Fish Tank Water Terrarium Temperature

The Zacro Digital Fish Tank Thermometer is one of the best selling aquarium thermometers. It is a very cheap item that can be left submerged in the fish tank so that you have a constant reading.


It features:

  • Temperature readings in both Fahrenheit or Celsius
  • LCD screen
  • Single power button – when turned on it will take immediate readings
  • Suction cup
  • Approx. 38 inch cable
  • Includes battery for immediate use
  • A 24 month warranty


FIND OUT MORE: Read The Reviews & See How Cheap This Thermometer Is!


2. American Thermal Liquid Crystal Aquarium Thermometer Horizontal


The American Thermal Liquid Crystal Thermometer is another popular aquarium thermometer. This one is applied horizontally to the side of your aquarium and takes a reading through the glass (or plastic).



  • High accuracy
  • Peel off and re-stick elsewhere on aquarium
  • Approx. 5 inches by 3/4 inch


TAKE A LOOK: At The Great Reviews & Spot The Price


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3. JW Pet Company Smarttemp Thermometer Aquarium Accessory

best fish tank thermometer in tank

The final fish tank thermometer we recommend here today is the JW Pet Company in tank thermometer. This product is secured to the inside of your tank with a magnet placed on the outside.


It features:

  • High accuracy of +/- 2 degrees
  • Easy to read number
  • Fahrenheit & Celsius
  • Made of glass
  • Cheap fish tank thermometer


CLICK THROUGH: To Find Out The Price & Read The Reviews


The Best Aquarium Thermometer


I hope you’ve been able to find the right thermometer for your set-up. Let us know in the comments below what your favorite thermometer is, and why you like it so much.


Thanks for joining us, and here are some further fish tank resources.


Fish Tank Resources



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