FREESEA Aquarium Fish Tank Heater: 100W Small Submersible Turtle Heater with Adjustable Temperature External Controller for Betta | Saltwater | Freshwater | 10-20 Gallon
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Availability:
In Stock.
Arrives
Thursday, Apr 23
Size: 100W(10-20gallon)
Features
- FREESEA Aquarium Heater: 100W betta fish heater, voltage: 110~120V, is suitable for use in 10-20 gal betta fish turtle tanks and aquariums. The power cord is 5ft, long enough for indoor use
- Double Safety Protection: When the top part of the turtle tank heater is out of water it will auto shut off. When the actual water temperature is higher than 94F, it will auto activate the overheating protection and stop heating
- External Controller: The betta fish heater is adjusted by an external controller, which you can mount on the outside edge of the tank. Its convenient to adjust temperature that range from 63F to 94F
- LED Temperature Display: Digital led temperature display shows the real-time temperature and error code on the screen. When the mini aquarium heater is heating, there indicator light above the digit is on red
- Excellent Service: The Heater of the FREESEA operate very stably under Fish Tank. If you have any questions about the Heater you received, please feel free to contact us at any time. 24-Hour Professional After-Sales Service
Is Discontinued By Manufacturer : No
Product Dimensions : 2.5 x 1.5 x 3.5 inches; 8.08 ounces
Item model number : FS28-100W
Date First Available : August 8, 2018
Manufacturer : FREESEA
Best Sellers Rank: #16,677 in Pet Supplies (See Top 100 in Pet Supplies) #29 in Aquarium Heaters
#29 in Aquarium Heaters:
Customer Reviews: 3.5 3.5 out of 5 stars (1,071)
Item Weight: 8.1 ounces
Manufacturer: FREESEA
Item model number: FS28-100W
Date First Available: August 8, 2018
Item Package Dimensions L x W x H: 5.63 x 3.7 x 2.64 inches
Item Dimensions LxWxH: 2.5 x 1.5 x 3.5 inches
Brand Name: FREESEA
Target Audience Keyword: fish
Color: Submersible Heater with External Controller
Size: 100W(10-20gallon)
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Thursday, Apr 23
Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Similar Products
Top Amazon Reviews
Size: 100W(10-20gallon)
I woke up this morning to my betta dead and the tank temp at 105.2 degrees Fahrenheit and the heater registering HH. I’ve bought two of these and the first one was great. But now both my self and my kid are heart broken to have our fish dead after having the new tank set up for less than a month to have my fish boiled alive. I’ll never buy this again. I’d rather go to the cheap not able to control undersize heaters. At least my fish won’t be dead.
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Reviewed in the United States on October 10, 2024 by Lady Andramada
Size: 100W(10-20gallon)
Purchased this tank heater in January of 2023. It has worked well since purchased, but has now failed on December 25, 2024 at almost the two year mark. What was concerning was not that it failed, but how it failed. The unit short circuited in the tank and burned up under water leaving the tank filthy with whatever plastic burned up. Also, whenever gas escaped in bubbles when it was burning up left a burned smell throughout one part of my house. Fortunely, I happend to be home and not far from the tank when this happened, so I was able to trace down the sound and smell and unplugged the unit. Hopefully, the fish in my tank will survive whatever chemicals were released into the water when the unit burned up. Maybe I just got a dud, but I would be cautious using this heater in any place that is unattended for any long periods of time.
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Reviewed in the United States on December 26, 2024 by J. Gomez
Size: 100W(10-20gallon)
highly recommend Freesea 100W fish tank heater. paired it with a SunSun JP-022 submersible pump to increase circulation, increase surface water agitation (increase oxygen transfer) and evenly heat the water. Also added a separate inexpensive thermometer to cross-check water temps. Completely satisfied. The ability to regulate the water temp at a push of the button is the best feature of the heater. Saved all my fish from ICK by giving me the ability to temporarily bump up the temp to 86 degrees and shutting off the lights for 7 days. I found I have to set the heater about 2 or 3 degrees higher than the desired temp I am trying to achieve in my tank.
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Reviewed in the United States on December 3, 2018 by Ritchie Rich
Size: 100W(10-20gallon)
I love the ability to be able to see what the temp is! Super easy to use. Little light shows up when it’s heating. Easy setup up. Doesn’t get to hot either. My beta loves to prop himself up on it!
Reviewed in the United States on March 21, 2025 by Amber Ireland
Size: 100W(10-20gallon)
Didnt last very long. My tank is at 65 when it should be at 78, Im glad I didnt wake up to my fish being dead. Never ran it dry, never let it over heat, just stopped working. UPDATE:I have now gone through 2 of these things, both with the same problem, they're just garbage. Dont buy one.
Reviewed in the United States on December 24, 2020 by Evan Stengel
Size: 100W(10-20gallon)
It worked great for a couple of months. I bought it in August of 2024, and on May 20th of 2025, the heater malfunctioned and killed all of my fish while I was at work. It cooked them alive. My whole room smells like dead fish now, and cleaning the tank smelt terrible I almost threw up.
Reviewed in the United States on May 21, 2025 by Claire Hoffmann
Size: 100W(10-20gallon)
I really liked this heater until it stopped working after 8 months!!
Reviewed in the United States on February 16, 2026 by LAURIE A GENTILE
Size: 100W(10-20gallon)
This one is recommended for small aquarium but I used in my 35 gal aquarium. Works fine to me. Only thing I totally dislike is: whenever there is short power interruption, the heater reset and started heating up and raise the aquarium temperature. Is there a solution for this or am I missing something here. This is not good. But, so far Its working.
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Reviewed in the United States on May 6, 2021 by Amazon Customer