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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 8,646 reviews
Condition: New
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Returnable until Jan 31, 2025

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Availability: In Stock.
Fulfilled by Amazon
Arrives Thursday, Jan 30
Order within 20 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: #9,006 in Pet Supplies (See Top 100 in Pet Supplies) #14 in Aquarium Heaters


#14 in Aquarium Heaters:


Customer Reviews: 4.2 4.2 out of 5 stars 8,646 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: Thursday, Jan 30

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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Top Amazon Reviews

    • Great heater for small aquariums
Size: 50Watt
I was a little nervous about this given some of the reviews, but pretty much every aquatic heater on Amazon has a decent amount of 1 star reviews. I'm using this in a 3 gallon tank I use for raising guppy fry until they are large enough to move to the larger aquariums I have for them. This has been amazing! I haven't modified it at all and used it for about a month now and I'm happy to report that every guppy survived. This heater does sometimes vary by 1 degree when the temperature drops below what it is set at but it quickly heats up again to the set temperature and it is never more than 1 degree lower which was not an issue for the babies. Honestly I prefer this to it always keeping the temp higher than what I set it at like some other models do since it pretty much guarantees that it will not cook your fish. None of my fish attempted to go behind the heater, so if I had a Betta I might place some netting around the suction cups on the back as one other reviewer did since Bettas do enjoy resting and hiding. Alternatively, I'd suggest giving your Betta more preferable resting places and hiding spots/keep the tank warm enough so he won't want to go behind the heater. ... show more
Reviewed in the United States on March 29, 2022 by Kindle Customer
    • Yank heater
Size: 50Watt
Works great easy to use and adjustable temperature is wonderful
Reviewed in the United States on December 18, 2024 by Cynthia Keutzer
    • Update: Be aware! Heat increase alows bacteria and fungi grow!!!
Size: 50Watt
Update: March 1st, after two weeks of using heat, my Bandit start developing darkish spot on few scales near tail fin. First I didnt worry, but then literally in a week, spot got bigger, it started bulging and developed white color stuff on top of black looking scales. I realized heat allowed either fungi or bacteria grow rapidly. His tank is about 3gal, he is alone, no other fish. Got Beta antifungal drops and aquarium salt. Took out all gravel. I use distilled water with Betta complete water conditioner. Now I am using API salt and Pimafix fungal infection drops. For about last 3 days Bandit is lethargic and most of the time stays low or hides in his house. He was happy for first two weeks with heater hanging around it all the time. I never had any fish or Betas before, I got him in August 2017, he was healthy and spunky til recently. Now he doesnt seem to be hungry, I watch him for about 15 min to swim up to eat. Right now he sleeps in his house and wont come out. I am heart broken to think that I might have make him sick by heating up water. I change water every couple weeks. Bandit has fresh 3 live Marimo balls, which suppose to absorb impurities. I have water pump for circulation, heater right now is on 72, just about low comfort level. I been using Antifungal drops since Mar 5th, dont see any improvement yet, but it doesnt seem getting worse either. I absolutely hate to think I might have caused him getting sick! I spent so much money on this little guy for his comfort, but I didnt think I could cause him harm =(''' Apparently I need to learn how to care properly for Bettas, since I never before had any fish. I got him in Petco in August 2017. When I walked by Bettas, they are in those tiney round containers laying there docile, he was the only one who went bezerk and started pounding on container, which made me look at him. He was looking at me and I heard this voice in my head " get me out of here!" I even looked around thinking where did this voice came from? Next thing I know I reach for his container...That day I dropped over 100bucks. 3gal tank, gravel, food, water drops etc. I came home thinking how did that happen and how do I best care for him? I went to Petco to buy litter for my Izabella and ended up with Bandit. I love him, he was happy in his new home, being able swim around. Now he is just lethargic, hiding in the house. I am sure heat has something to do with it. Now I am trying to reverse damage. For people like me, who dont know much about Betas, this is lesson to be learned. Original review: I got this heater Feb 14th, plugged in and it heated up quite fast, I would say in 30min temp was warming to his comfort level. I set it for 78F. I have one Beta boy, on these cold arctic days water temp got below his comfort zone, as per thermometer. My Bandit was laying low and wouldn't swim around much. When I plugged in heater, he was drawn to it immediately, he was staring at it for a while and then just hanging around it for warmth. My poor Beta was cold without heater =(''' Now that water temp is comfortable for him, which is 22-26C or 72-80F, I can see his spunky self swimming around happy! His water thank holds almost 4gal, I have gravel, water pump, not filter, and heater, and I can see my Bandit is happy. Now he has better appetite also, and I don't have to watch him for 15min before he swims up to eat, now he eats right away. I realized that he wasn't comfortable in colder temps and I am very glad I got this heater for him! Very well worth the money thus far. I wish there was option for C temps, but its only for F. Instructions are very simple, immerse heater all the way into water, plug in and press temp button. I am glad for this purchase and my Bandit is happy! I recommend this heater. 4 stars only because no C option, otherwise 5 stars. ... show more
Reviewed in the United States on February 17, 2019 by Ms.Smarte Blonde
    • 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
    • Stopped working after 4 months
Size: 100Watt
Look I know these things aren't meant to last forever but I certainly expect it to work for AT LEAST a year. I bought this about 3-4 months ago and at first it worked great but just last week it completely malfunctioned. The worst part about it is that instead of turning off and just not turning back in like any other appliance, this heater started getting hotter and hotter to the point that it reached 100 degrees. I didn't notice until I saw bubbles appearing in my aquarium. Luckily I was home and noticed it happening. No fish deaths. But the fact that is OVERHEATED like that is just dangerous. Do what you will but I wouldn't trust this product. ... show more
Reviewed in the United States on October 6, 2024 by Emily

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