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FREESEA Aquarium Fish Tank Heater: 50W Small Submersible Turtle Heater with Adjustable Temperature External Controller for Betta | Saltwater | Freshwater | 1-10 Gallon

  • Based on 8,678 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Thursday, Jan 30
Order within 20 hours and 46 minutes
Available payment plans shown during checkout

Size: 50Watt


Features

  • FREESEA Aquarium Heater: 50w betta fish heater, voltage: 110~120V, is suitable for use in 1-10 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

Voltage: 110 Volts


Item Length: 3.5 Inches


Brand: FREESEA


Color: Submersible Heater with External Controller


Wattage: 50 watts


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 2.5 x 1.5 x 3.5 inches; 8.15 ounces


Item model number ‏ : ‎ FS28-50W


Date First Available ‏ : ‎ September 17, 2017


Manufacturer ‏ : ‎ Guang Zhou City Freesea Industrial Co.,Ltd


Best Sellers Rank: #7,361 in Pet Supplies (See Top 100 in Pet Supplies) #18 in Aquarium Heaters


#18 in Aquarium Heaters:


Customer Reviews: 4.1 4.1 out of 5 stars 8,678 ratings


Voltage: 110 Volts


Item Length: 3.5 Inches


Brand: FREESEA


Color: Submersible Heater with External Controller


Wattage: 50 watts


UPC: 722970219243


Manufacturer: Guang Zhou City Freesea Industrial Co.,Ltd


Item Weight: 8.1 ounces


Item model number: FS28-50W


Date First Available: September 17, 2017


Item Package Dimensions L x W x H: 5.55 x 3.7 x 2.8 inches


Item Dimensions LxWxH: 2.5 x 1.5 x 3.5 inches


Brand Name: FREESEA


Target Audience Keyword: fish, fish tortoise


Size: 50Watt


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
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

  • 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

  • Finally found a heater that works!
Size: 50Watt
This is the third type of heater I have tried for my 5 gallon betta tank. This one works! It's keeping my temperature at a steady 78.5*. Now, there is a caveat: the temperature is set for 82*, so it doesn't match my separate glass thermometer reading, but I don't mind adjusitng it a few degrees higher. Also, there is a large red temperature gauge on the heater itself which is visible at night. But the heater is fairly small and easy to use. I would buy this brand again. ... show more
Reviewed in the United States on December 21, 2023 by smilingswan

  • Works perfectly
Size: 50Watt
I have 2 of these in outdoor water bowls for animals. This last week we had temperatures down to 17 degrees Fahrenheit, with 7” of snow and none of these bowls froze. It’s not a typical use for them, but they work great. This model even has a feature that shuts it off if it gets pulled out of the water. Which happens with animals, so that’s a great feature. ... show more
Reviewed in the United States on January 14, 2025 by Ryan

  • Lasted Almost Two Years, Then Failed
Size: 100Watt
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. ... show more
Reviewed in the United States on December 26, 2024 by J. Gomez

  • Fish boiled alive overnight: dead
Size: 100Watt
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. ... show more
Reviewed in the United States on October 10, 2024 by Lady Andramada Lady Andramada

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