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Fluval M50 Ultra-Slim Submersible Aquarium Heater – 50W Underwater Heater for Aquariums up to 15 Gal.

  • Based on 4,947 reviews
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Availability: In Stock.
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Arrives Friday, Feb 7
Order within 9 hours and 1 minute
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Size: M50


Features

  • Modern Aesthetic: M-Series heaters combine modern aesthetics with reliable Italian construction. Employing an ultra-slim profile, these heaters are a welcome departure from traditional, bulkier designs.
  • Reflective Design: This heater is encompassed in a heat-and-shock resistant reflective Borosilicate glass tube, which allows it to reflect the surrounding aquarium colors, allowing it to blend in with the environment and enhance overall aesthetics.
  • Temperature Control: Computer-calibrated thermostat has an easy-to-adjust temperature control dial and an on/off blue indicator light to display when its in use.
  • Slim Profile: Ultra slim design allows for easy installation in your aquarium tank.
  • Recommended Size: M50 underwater heater is ideal for freshwater and saltwater aquariums up to 15 gallons. Each M-Series heater comes with a 3-year limited warranty.

Description

The Fluval M Submersible Aquarium Heater’s quality European manufacturing utilizes superior components and construction. The Fluval M50 Submersible Heater is ideal for use in freshwater and marine aquariums up to 15 gallons and has a temperature range of 66-86 degrees Fahrenheit. This sleek, compact heater can be trusted for exceptional performance and unsurpassed reliability. Unique only to the Fluval "M" series the reflective technology equipped in the Fluval M Submersible Aquarium Heaters helps maintain the aquariums' natural look as the heater reflects the colors of the surroundings.Fluval first broke onto the aquatic scene in 1975 by introducing the world’s first 3-stage filter with synchronous motor technology – a landmark breakthrough that is still applied in the industry today. Since then, Fluval has built a legacy around this pioneering spirit, relentlessly adapting in a changing world to launch innovative aquarium products that remain at the forefront of technology, and which set the bar in quality, style and functionality. Above and beyond its manufacturing role, Fluval prides itself on its charitable and educational efforts that give back to the fishkeeping community, whether it means helping to fund the protection of wild coral reefs or jumping on a plane to document endangered fish species halfway around the world. Fluval’s mission is not just about building products that mimic the natural world, but inspiring aquarists of all skill levels to enjoy and respect the hobby for generations to come.

Brand: Fluval


Target Species: Fish


Material: Ceramic, Borosilicate Glass


Special Feature: Reflective Technology


Product Dimensions: 1.8"L x 4.8"W x 14.8"H


Item Weight: 9.86 ounces


Specific Uses For Product: Aquarium Heating


Style: M50


Included Components: Fluval M50 Submersible Glass Aquarium Heater (50 watts)


Manufacturer: Rolf C. Hagen (USA) Corp.


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 1.8 x 4.8 x 14.8 inches; 9.86 ounces


Manufacturer recommended age ‏ : ‎ 1 month and up


Item model number ‏ : ‎ A781


Date First Available ‏ : ‎ August 19, 2004


Manufacturer ‏ : ‎ Rolf C. Hagen (USA) Corp.


Country of Origin ‏ : ‎ Italy


Best Sellers Rank: #5,546 in Pet Supplies (See Top 100 in Pet Supplies) #8 in Aquarium Heaters


#8 in Aquarium Heaters:


Item Weight: 9.9 ounces


Manufacturer: Rolf C. Hagen (USA) Corp.


Country of Origin: Italy


Item model number: A781


Date First Available: August 19, 2004


Item Package Dimensions L x W x H: 14.61 x 4.76 x 1.77 inches


Item Dimensions LxWxH: 1.8 x 4.8 x 14.8 inches


Item Weight: 9.86 ounces


Brand Name: Fluval


Target Audience Keyword: algae-eaters, bottom-feeder-fish, mollusks, goldfish, octopuses, snails, fish, cichlid-fish, sharks, invertebrate-fish, rays, betta-fish


Directions: Follow individual packaging instructions


Warranty Description: 3 years; The Fluval M series Submersible Aquarium Heater is guaranteed for defective parts and workmanship for a period of 3 year. We reserve the right to repair or replace, at our option. This guarantee excludes damage, breakage of the glass tube or injuries resulting from negligence or other misuse. This warranty does not include responsibility for animate or inanimate matter contained in the aquarium and is limited to the heater unit only. This appliance is factory sealed, tampering will void warranty.


Size: M50


Material: Ceramic, Borosilicate Glass


Age Range Description: All Life Stages


Number of Items: 1


Style: M50


Breed Recommendation: All Breed Sizes


Included Components: Fluval M50 Submersible Glass Aquarium Heater (50 watts)


Specific Uses for Product: Aquarium Heating


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Friday, Feb 7

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


  • works as described
Size: M150
I use this heater in my 45 gallon freshwater aquarium. it's working great and holding the temperature of the tank well. suction cups are very strong and have not moved or slid on the glass at all. I have it set to 75 and it is reading very accurately.
Reviewed in the United States on April 22, 2024 by Stephen

  • Very accurate and user friendly
Size: M150
Love this heater, super accurate, works flawlessly, no fluctuations in temps in 20 gallon long tank. The blue light is not annoying like the old red ones, its also not very visible in daylight. Comes on and off with heater thermostat. I would definitely buy this again. Ive used a lot of heaters over the years, so far this one is very good. ... show more
Reviewed in the United States on May 14, 2024 by Elizabeth Jackson

  • Works well.
Size: M150
It keeps a steady temp that matches the setting. It was longer than I expected
Reviewed in the United States on April 13, 2024 by mark s.

  • Great product, sub-par packaging.
Size: M150
I don’t have anything but positive things to say about the fluval heater, this heater has always performed. But whoever packed this for shipping really needs a class on how to pack a fragile, glass, heater used for someone’s investment. The heater was out of the factory package, loose in the bottom of the box, probably flopped around its trip to delivery. Minimal bubble plastic just kinda in there. I’m surprised it worked when I plugged it in and only time will tell for how long. ... show more
Reviewed in the United States on November 21, 2023 by Phisty Probe

  • Maintains desired temperature but temperature dial doesn't seem accurate.
Size: M100
I’m a home-brewer and I bought this heater to help control temperature of my fermenting wort. So far this unit seems to be working pretty well, except that the temperature set on the heater dial isn’t the actual temperature of the water-bath I have my fermenter sitting in; seems to be off about seven degrees or so. Some background info: I have a 17 gallon tub that I put my fermentation vessel in and then submerge it in water; the heater is supposed to allow me to maintain a specific temperature for fermentation. I’ve been using this heater for about eight days, while I’m fermenting a saison that needs to maintain a target temperature of 75 degrees; while I’m able to maintain a 75 degree temperature the temperature dial on the heater is set to 82-83 degrees. I’ve been taking temperature readings twice a day with an accurate handheld digital thermometer, so I can say with good evidence that there’s a definite discrepancy between the set temperature and the actual temperature. However, I’m not sure what affect ambient temperature has on the heater. Right now I have my fermentation setup in my basement, where the ambient temp is right around 65-66 degrees and the tub I use for my water bath is sitting on a concrete floor. I assume the heater needs to be turned up a bit more to help compensate for the cooler ambient air and to maintain the desired 75 degree fermentation temperature. On my next brew I plan on getting the water tub off the concrete floor and wrapping insulation around it, hopefully that will help in having a more accurate temperature reading on the heater dial. Overall I’m pretty happy with the performance of this heating unit, I know I can reach and maintain the 75 degree temperature I need right now, but I have some concerns about being able to reach fermentation temperatures in the upper 80 degree range. That being said, I will do some more testing and see if this issues is due to operator error and see if I can get the temperature on the dial to be closer to the actual temperature. ... show more
Reviewed in the United States on November 25, 2013 by Shannon

  • Has not let me down
Size: M150
I have several M series heaters. They have all been accurate and reliable. Big and shiny and not for aquascapers, but great for people who just keep fish.
Reviewed in the United States on February 18, 2024 by Nathan Avery

  • Working fine for years
Size: M200
I bought this as a direct replacement for the one currently in my tank. The one in use is about 5 years old and still works great. If/when it finally breaks, I'll be sticking with Fluval for heaters.
Reviewed in the United States on April 21, 2024 by Jeniffer DeVries

  • Very good heater!
Size: M100
I have this heater in my 30 gallon aquarium and it does a great job and keeping temp. I like the mount that comes with it way more than other suction mounts that come most other heaters. Very sturdy and made very well. I would definitely buy again!
Reviewed in the United States on February 23, 2024 by Dean

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