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FREESEA 100W Mini Aquarium Fish Tank Heater with LED Temperature Display for Betta Fish, Frogs, Newts & Turtles

  • Based on 7,739 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Wednesday, May 22
Order within 18 hours and 50 minutes
Available payment plans shown during checkout

Size: 100Watt


Features

  • Temperature range: 59F~94F, display Fahrenheit F, this heater is designed for10~20 gallons tank. Upgrade function: The heater will auto shut off when it is out of water and turn normal when fully in water again.
  • Automatic constant temperature function, when water temperature reaches to specified temperature value, heater will automatically stop heating, when water temperature is lower than the set temperature, heater will automatically start heating.
  • Touch button, cyclic adjust temperature , easy to use and Safety.
  • Note:this heater is 100% submersible use only, during its heating time, heater must be 100% submerged into the water.
  • SATISFACTION GUARANTEEDGain the confidence to go hard with us! Our Aquarium Heater is built with durability in mind and safety for every design, In the remote possibility that youre not satisfied with our product, just contact us, and we will gladly give you a new Aquarium Heater replacement. 12 Month Warranty and 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 6, 2018


Manufacturer ‏ : ‎ FREESEA


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, May 22

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


  • Does not read correct temp
Size: 100Watt
Both of mine do not read the correct temp. It is off a few, especially near the higher ranges. It's fine if you don't need an exact temp and need it within 70-80 degrees. I tried bumping it up past that and my thermometer kept reading higher but the thermometer said it was several degrees cooler. I was using it within the proper tank size and even placed the thermometer directly next to it to see if it was accurate and not just the water/distance. I did end up buying another since these are outliving other ones I have and don't take up a lot of space/ aren't tall. ... show more
Reviewed in the United States on February 19, 2023 by Goose Goose

  • Appreciate the digital temp setting and display
Size: 75Watt_
I wasn't sure my old cheap tiny heater was really working anymore, so I shopped around for a new one and found this. Display temp matches the temp strip I have on tank. Flora and fauna seem happier now with the more stable temp set based on tanks occupants preferences (about a degree or two warmer than previous one which could not be set to anything in particular). Digital display also makes it really obvious to see if a certain kid has switched off the surge suppressor that everything is powered through. :/ I've had this installed a few months and overall happy with purchase. ... show more
Reviewed in the United States on March 11, 2023 by Sat Kartar Khalsa

  • 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 for my Betta
Size: 75Watt_
The heater seems to be working wonderfully. You can set the temperature with an easy click of a button and it tells you what the temperature of the water is in real time. It works fantastic for my ten gallon betta tank.
Reviewed in the United States on April 1, 2023 by Raine Eaton Raine Eaton

  • Good heater for my 3.5 gallon tank
Size: 50Watt
I like the heater, it heats the water well and warm enough for my betta. It takes a whole chunk of space, but it does it’s job well so far. I also like that it is digital.
Reviewed in the United States on March 23, 2023 by sushovan

  • Works but Temperature Varies
Size: 75Watt_
I put this heater in my 25 gallon tank. It works fine, but it turn on and off constantly (about 2 cycles per minute). The temperature read out goes from about 1 degrees below the set point all the way to about 4 degrees over the set point during a cycle. I have concerns it will fail early.
Reviewed in the United States on February 16, 2023 by Amazon Shopper

  • Works very well
Size: 50Watt
Bought for 5 gallon Betta tank. Suctioned to the glass very well, and love that I can see the current temp at all times. Does not interfere with fish swimming around. Would definitely order again if needed.
Reviewed in the United States on March 18, 2023 by JLD

  • Has been working fine for weeks, but the suction cups are terrible
Size: 50Watt
I purchased this heater about a year ago as a backup in case one in use quit, which one did a few weeks to a month or so ago. So far, I have no complaints about its ability to set and maintain a temperature. However, the suction cups are really terrible -- even on squeaky clean glass. After trying again and again to get it to stick, I finally yanked it out and replaced the suction cups it came with, with a set I'd taken off the old heater. The used suction cups are doing the job the Freesea ones wouldn't. ... show more
Reviewed in the United States on January 9, 2023 by V. Hartman

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