Underwater Treasures Digital Fish Thermometer

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$2.14 Chewy Price
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About This Item

Details

  • Displays temperatures in both Fahrenheit and Celsius.
  • Easy-to-read green indicator lets you monitor your tank’s temperature at a glance.
  • Temperature readings range from 18–34 degrees Celsius and 64–93 degrees Fahrenheit.
  • Durable design adheres directly to your tank’s exterior.
  • Suitable for use with freshwater or saltwater tanks (sold separately).

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Reviews
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3.9
Rated 3.9 out of 5 stars
34 Ratings
Terms & Conditions

10 Customer Reviews

Rated 5 out of 5 stars
By Clinton on Dec 22, 2025

Great price

Great price znd it works great

Great price znd it works great

Rated 5 out of 5 stars
By Diana on Jun 1, 2025

Pretty accurate

I was having a difficult time finding a glass thermometer for inside my tank so I got these. I have been double checking them with a food thermometer and so far

I was having a difficult time finding a glass thermometer for inside my tank so I got these. I have been double checking them with a food thermometer and so far they have been pretty accurate.

Rated 1 out of 5 stars
By janice on Nov 24, 2025

Didn’t work

Waste of money

Waste of money

Rated 3 out of 5 stars
By Gregory on Feb 5, 2025

Liquid crystal thermometer

It’s simple, but unfortunately, it’s hard to see

It’s simple, but unfortunately, it’s hard to see

Rated 3 out of 5 stars
By Kimberly on Nov 16, 2024

Just ok.

Just ok, mine didn't show temperature that long, in this name brand, don't know why?

Just ok, mine didn't show temperature that long, in this name brand, don't know why?

Rated 1 out of 5 stars
By NOLAStar78 on Nov 17, 2023

I did not pay attention

I greatly dislike that the Fahrenheit reading was so tiny. I wanted to make seeing the temp as easy as possible on myself, but this one did not do that. Also it

I greatly dislike that the Fahrenheit reading was so tiny. I wanted to make seeing the temp as easy as possible on myself, but this one did not do that. Also it cannot be moved at all without breaking it. I guess I should have looked at it better but it never occurred to me that the Celsius reading would be the main reading. Since reading it was impossible anyway I guess tearing it up didn't matter. I bought a new one that is easier to read. I have a digital thermometer and my heater also tells the water temp, but I always place one of these out of the way - on the side, towards the back as an old fashioned backup.

Rated 1 out of 5 stars
By Bill on Jan 17, 2024

External temp gauge

The "green" indicator is extremely difficult to discern from the black background making reading the temperature more of a "guess".

The "green" indicator is extremely difficult to discern from the black background making reading the temperature more of a "guess".

Rated 5 out of 5 stars
By MAR on Nov 28, 2023

Affordable & simple Thermometer

Arrived safely, as described, works fine, does the job. I've been using this peel on glass thermometer since 2008. It's pretty accurate. I've tested it with automotive

Arrived safely, as described, works fine, does the job. I've been using this peel on glass thermometer since 2008. It's pretty accurate. I've tested it with automotive temperature gun. It's within 2-3 degrees accurate.

Rated 5 out of 5 stars
By CHERYL on Jan 12, 2024

Water temperature

Works very well. Rather the fahrenheit was bigger and Celsius smaller.

Works very well. Rather the fahrenheit was bigger and Celsius smaller.

Rated 3 out of 5 stars
By Loveaferret95 on May 15, 2023
Top 250 Contributor

Not easy

This is hard to see

This is hard to see