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FREESEA Aquarium Fish Tank Heater: 50 | 100 | 300 Watt Adjustable Thermostat with 2 Suction Cups & Thermometer for Betta Tank | Saltwater Tank | Aquarium | Coral Tank

  • Based on 714 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Saturday, May 25
Order within 20 hours and 4 minutes
Available payment plans shown during checkout

Size: 300 W


Features

  • 300Watt Heater: This Aquarium heater is suitable for 40 to 60 gallons aquariums, Length - 12.6 inch,voltage 110-120V, power cord is 4.0 ft, please choose the right wattage aquarium heater according to our size chart.
  • Temperature Range: 64F~93F , It is very easy to adjust the temperature you need, we also deliberately give each customer a free diving thermometer, you can observe the water temperature of the fish tank at any time.
  • Intelligent Temperature Control: 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. Furthermore, Automatic safety shut-off feature, and overheating protection.
  • High Quality: This upgraded aquarium heater now updated for 2mm durable Quartz Glass, which is pretty shatter-proof and blast-proof and prevents electricity leakage. And the stronger protective container updated for Anti-melting anti punching double sealed material, it is scald-preventing for your pets and your safety, suitable both for fresh and salt water.
  • Satisfaction Guaranteed: Gain 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.

Description

Read more Creating and maintaining perfect conditions for your pet fish can be difficult. Some species prefer colder aquarium water, while others prefer warmer temperatures. No matter what your fish like, it’s vital to frequently monitor the temperature of their habitat and maintain the optimum conditions. With a good FREESEA aquarium heater, you’ll easily monitor the water temperature and adjust it if needed, thereby keeping your fish safe and healthy. FREESEA Aquarium Submersible Heater Key Features: 1.Temperature range: 64°F~93°F , It is very easy to adjust the temperature you need. 2.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. POWER: 300 Watt VOLTAGE: 110V-120V, 60Hz APPLICATION:40-60 gallon fish tank POWER CORD: 4.9 ft HEATER lENGTH: 12.6 inches Read more Read more Read more 100% is submersible heater, and it should be installed on the inner side of fish tank. 100% is submersible heater, and it should be installed on the bottom of fish tank. It is forbid for exposing some main body part of heater on water when using. The water level of fish tank cannot very low, as it is easy for heater to exposed on water. Read more NOTE: Please make sure the heater in 100% submerged while you using it ! ! ! Customers who buy this item also buy the following products.↓↓↓ View Purchase View Purchase View Purchase View Purchase View Purchase View Purchase Brand Name FREESEA FREESEA FREESEA FREESEA FREESEA FREESEA Product Name Aquarium Heater Submersible Water Pump Fish Tank Water Pump Aquarium Heater Water Pump Size 50W 550GPH 30W 1.2 Gallon 160GPH 25W 95GPH


Product Dimensions ‏ : ‎ 13.39 x 1.18 x 0.79 inches; 10.58 Ounces


Date First Available ‏ : ‎ September 7, 2020


Manufacturer ‏ : ‎ FREESEA


Best Sellers Rank: #10,893 in Pet Supplies (See Top 100 in Pet Supplies) #28 in Aquarium Heaters & Chillers


#28 in Aquarium Heaters & Chillers:


Customer Reviews: 4.2 out of 5 stars 714 ratings


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, May 25

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


  • Melted and almost killed fish
Size: 50 W
Began to melt due to it overheating and started to boil my fish tank.
Reviewed in the United States on December 4, 2020 by Sarah Hostetter

  • It works... Sorta.
Size: 50 W
I have this heater in an 8.5 gallon tank. Ambient temperature is 68°. The tanks is located on a granite countertop. While the heater works, I can't say that it works too well. For starters, when you get the heater, ignore the temperature dial on the top. It's absolutely useless. If I were to set it to 78°, my tank would be at 85°+. Even after setting the temp to shut off at 78, the temperature swings from 72°-78° which makes me a bit uncomfortable. I don't recommend this if you're keeping fish with sensitive temperature requirements. As it stands, that 6° window is just barely enough for the few guppies, tetras, shrimp, and plants I have. I will likely be setting up a spare thermostat to manage temps more accurately. ... show more
Reviewed in the United States on January 28, 2021 by KayCee

  • SIZZLES WHEN PUT IN WATER!
Size: 50 W
Your browser does not support HTML5 video. DO NOT BUY THIS! It burned my finger, I have a physical burn on my finger because of it! I’m so glad I touched it before I put it in my fishes tank! It sizzles when I put it in water!!!!!! This is so unsafe!
Reviewed in the United States on January 26, 2021 by Amazon Customer

  • A Heater That Does Not Heat
Size: 50 W
This 50W FREESEA heater arrived from Amazon today. It was purchased to maintain 84F in a10 gallon aquarium used as a quarantine tank. The tank was using a borrowed 150 W heater before the FREESEA heater arrived. Upon its arrival this FREESEA 50 W heater (rated to heat 5 to 15 gallon aquariums from 64 to 93F) was fully submerged in the tank before being plugged in and the borrowed heater removed. The new FREESEA heater began cycling on and off within minutes of being plugged in After one hour I checked the aquarium's temperature and found it had dropped 2 degrees to 82F (ambient room temperature is 68F). Within four hours of its installation the heater continued to cycle on and off, but the temperature in the tank had now dropped to 78F. I immediately replaced the FREESEA heater with a locally purchased Eheim heater. The temperature in the tank is now being properly maintained and the defective FREESEA heater is being returned to Amazon. ... show more
Reviewed in the United States on March 2, 2021 by Scotishburr

  • Do not buy this!!!!!!
Size: 50 W
Poor quality. Did not work as it supposed to And less than a month now , i noticed that sparkles came off of it and almost hurt my fish and it did hurt my snail. As snail climbed up on it, two sparkles shot at it, caused it to fall. And my snail had beautiful antenna, it got damaged from it. Horrible! Im glad i witnessed it and turned off immediately, god i cant and dont want to imagine what could have happened if i didnt notice. Im contacting amazon customer service on this matter and the associate escalated this issue. the team will reach out to me. I am returning this!!!!! Buyer be aware!!!!!!!!!!!!!!!!!!!!! ... show more
Reviewed in the United States on May 30, 2021 by Amazon Customer

  • Amazing quality and works well for price
Size: 50 W
After looking at the rip-offs at petco I decided to go online and take a chance for my fish. I've gone through so many of these and this one is great. For the price it's amazing. I have a 10 gallon tank with several fish in it and I like to keep it around 79 to 82 degrees for which this is perfect. I submerged it near the bottom with suction cups and I haven't had any issues so far in several weeks. It stays stuck. The cord appears to be made well. I just had to take one star off because the little temperature gauge that came with it does not work. Maybe it was broken but I really would have liked to have it. ... show more
Reviewed in the United States on January 9, 2021 by I.B.

  • Good standby
Size: 50 W
My first nano aquarium had a different model by this company and it did good. Temps varied within a couple degrees, which is stressful to my fish...but it wasn't bad. For my second nano tank, I tried a "name brand" heater from a local chain store. It quit heating completely after three days. I then ordered another "name brand" from Amazon and that one was overheating even though it was the correct size. I finally decided the couple degree variation on this brand was acceptable. It took a few days to dial in the temp. I had to set it lower than what I wanted to get it to hold fairly steady in the 78.5-80°F range. But my tank is now finished it's first cycle and the temps are holding fairly steady. I feel confident this won't stress my fish too much and thank goodness it won't cook him. ... show more
Reviewed in the United States on April 7, 2021 by Orlando Foodie

  • Please listen don’t buy
Size: 300 W
First thing, I don’t don’t how this product is rated so high. I agree with all the lower reviews. My best guess is that the price is really good they opened it up put it in the tank saw the light come on and wrote a good review. This heater is unreliable. The temperature is way off. Set for 82 left over night and the temp was closer to 70 degrees. I knew better than going cheap with something like this. I have pretty expensive turtles and I’ve seen some of the reviews about the heater cracking and killing fish. I would not doubt this. Just buy a more expensive high quality heater and save yourself the headache and some dead animals. ... show more
Reviewed in the United States on August 12, 2021 by Amazon Customer

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