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    FREESEA

    FREESEA Aquarium Fish Tank Heater: 100W Small Submersible Turtle Heater with Adjustable Temperature External Controller for Betta | Saltwater | Freshwater | 10-20 Gallon

      • Based on 8,720 reviews
    Condition: New
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    Availability: In Stock.
    Fulfilled by Amazon
    Arrives Tuesday, May 13
    Order within 6 hours and 50 minutes
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    Size: 100Watt


    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
    • 12-month Warranty: We are committed to providing high quality products and better service with a 12-month warranty. If you have any questions about the turtle heater you receive, please feel free to contact us

    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: #15,405 in Pet Supplies (See Top 100 in Pet Supplies) #24 in Aquarium Heaters


    #24 in Aquarium Heaters:


    Customer Reviews: 4.1 4.1 out of 5 stars 8,720 ratings


    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: 100Watt


    Frequently asked questions

    If you place your order now, the estimated arrival date for this product is: Tuesday, May 13

    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.

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    Leasing options through Acima may also be available during checkout.

    Learn more about financing & leasing here.

    Similar Products

    Top Amazon Reviews

      • Great
    Size: 50Watt
    I recently purchased the FREESEA Aquarium Fish Tank Heater, and it has been a fantastic addition to my aquarium setup! This 50W submersible heater is specifically designed for small tanks, and it’s perfect for maintaining the right temperature for my betta fish and other aquatic friends. One of the standout features of this heater is its adjustable temperature external controller. Setting the desired temperature is a breeze, and the clear display allows me to monitor it at a glance. I’ve noticed that my fish are much more active and healthy since I started using this heater, which I attribute to the consistent temperature it maintains. The design of the heater is compact and sleek, making it easy to fit into my 1-10 gallon tank without taking up too much space. It’s also submersible, which means I can place it exactly where it’s needed for optimal heating. The installation process was straightforward, and I appreciated the included suction cups that keep the heater securely in place. I was also impressed by how quickly the heater warms up the water. It doesn’t take long to reach the desired temperature, and I feel confident that my fish are comfortable and safe. The heater has built-in safety features, such as over-temperature protection, which provides additional peace of mind. What I love most is its versatility; this heater is suitable for both freshwater and saltwater tanks, making it a great option if I decide to diversify my aquarium in the future. The quality of the materials used feels solid, and I expect it to last a long time. Overall, the FREESEA Aquarium Fish Tank Heater is an excellent choice for anyone with a small aquarium. It offers reliable heating, easy temperature control, and peace of mind for fish owners. I highly recommend this heater for keeping your aquatic pets happy and healthy! ... show more
    Reviewed in the United States on November 5, 2024 by C
      • Nice Little Heater
    Size: 50Watt
    Nice little heater. I like the digital readout and ease to use. It can hear a 38 gallon tank to 79F if the ambient temp in the room is 70. It struggled when the ambient room temp was 65 so I used two of them then.
    Reviewed in the United States on February 24, 2025 by clubnp
      • Works really well, thermometer is off
    Size: 50Watt
    The media could not be loaded. Update: the heater stopped whistling and making weird noises, and had been working very well for a while. I like it. Only 4 stars because the thermometer is off by 4-6 degrees When I got this product, within the first couple days it was working good. The temperature was ~6 degrees higher on the thermometer than it actually was so I had to adjust the target temperature hotter than I would to get it right. But now after installing it 6 days ago, it’s began this loud and unpleasant(at the least for my fish) whistling noise when it starts heating. I can see him hiding away whenever it turns on. I’m not happy with how it’s stressing him out, but also I don’t want it to malfunction and kill my fish :( There was also a grinding noise I heard once coming from the heater a couple days before but it subsided. I read online it could be a leak, but I took the back off of the heater and submerged it in water and saw no bubbles, so I really don’t know what it could be. If this issue doesn’t resolve quickly I think I’ll be returning this one and getting one from my local pet store. ... show more
    Reviewed in the United States on December 17, 2020 by David T.
      • Would def buy again
    Size: 100Watt
    Great product, it keeps the aquarium nice and cozy. The only issue is the suction cups aren’t great.
    Reviewed in the United States on April 18, 2025 by Amber
      • IT KILLED ALL MY FISH!
    Size: 75Watt_
    Review Image by Surf and you shall find Surf and you shall find
    I bought this on October 27, 2024. It was working fine until last night. It malfunctioned and KILLED ALL MY FISH overnight!! It was set at 72 degrees! The button to change temp was not exposed. This morning it was glowing orange and with my temp gun it was 122 degrees!!!!!! 6 months old and apparently the safety shut off doesn’t work WTF! I have had different heaters in the past and this NEVER HAPPENED! $150 of fish GONE! NEVER BUY FROM THIS PROBABLY China made company! ... show more
    Reviewed in the United States on April 3, 2025 by Surf and you shall find Surf and you shall find
      • good help
    Size: 75Watt_
    we used this heather before , ; and it works pretty well; we have it in outside water tank for turtles mostly in winter time. and sometimes we found them on top of it . this means that it keeps them warm enough . When is too cold we put them inside the house and in the summer no need . we just have to chenge them after rwo or three years depending of the used. we keep it on, all day during the cold. the tank is 25 gallons. ... show more
    Reviewed in the United States on December 29, 2024 by ElizaMe
      • Not good enough to keep
    Size: 75Watt_
    This was larger than I expected, which is my fault. They give an accurate measurement, I get other ideas in my head. Then, I hadn't thought about how obtrusive the lighted digital temperature would be in the tank. It can't be dimmed or turned off. Finally, the temperature is off. It consistently reads 4° higher than the actual temperature according to two other thermometers. I guess this isn't terrible. Consistently 4° off still let's you keep a consistent temperature. It was just too many little things for me. I will be returning it. ... show more
    Reviewed in the United States on April 16, 2025 by Collins Family
      • Beta approved!
    Size: 100Watt
    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

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