Hydor USA

Hydor THEO Heater 300 Watt

$25.99  

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In stock in our East and West Coast warehouses

HD11402


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Theo 300W For Aquariums 53–80 gallons
New aquarium heater functioning with the exclusive PTC (Positive Thermal Coefficient) technology.


The Hydor Theo heater line features PTC patented thermal technology which makes it among the safest aquarium heater lines on the market. UL Listed by design, not by the use of accessories. Made from specially engineered shatterproof glass which, while not unbreakable, is designed to resist breakage in most normal aquarium situations. Highly accurate due to the use of precise micro-switch technology. For use in freshwater and marine aquariums. The 50W & 100W/150W models, at 7" & 8.9" respectively, are among the smallest sized heaters on the market. The Theo "minimum water line" requirement must be followed for proper operation.

Features
  • The first shatter-proof heater thanks to the peculiar glass tube.
  • Maximum security: THEO is shock resistant thanks to the PTC heating element and the shatterproof glass tube.
  • Free positioning in aquarium with supplied suction cups.
  • Self-limiting: the patented PTC heating system guarantees operation in complete safety because in case of dry running there is no danger for damage.
  • 15.5" length
  • Two year manufacturer`s warranty.

Product Manuals & Documentation

Hydor THEO Heater 300 Watt

Owner's Manual available for download in Adobe PDF file format

Manufacturer Info

Hydor has been producing a comprehensive range of equipment for aquariums and ponds since 1984 and offers the best in high-technology for the creation of a living ecosystem at home. The factory has developed thanks to the engineering competence of its founder and its continuous growth is based on the investment it has made in research and the development of innovative technical appliances. A competitive and dynamic structure of more than 150 employees regularly engages in the implementation of products which meet the demands of 50 nations and keep pace with the evolution of the world markets. The global quality is not a simple working method but a daily expression of mind.

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9 Questions
Displaying questions 1-9
 
Q
underwater / vertical or can i lay it down
Can this heater be fully submerged under water? Can I either have it vertical or can i lay it down in a sump?
Asked : Feb 25, 2017
By : Blackley, Corona
 
 
 
A
Thank you for your question. This heater can be fully submerged and operated in a horizontal or vertical position.
Answered : Jun 27, 2017
By : MD Tech
 
 
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Overall, others give this:

  • 3.0

2 Reviewers (0%) would recommend this

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3
3.0
Good but..

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REVIEW
Great heater when it works. I had to turn mine down to 76 to keep the tank at 80. any higher that 76 and it heats the water to 90 degrees!
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3
3.0
Fine if you have a controller
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PROS
Cheap, small
CONS
don't trust them
REVIEW
Ive had two of the three fail. One in less than a year and the other in a year and a half. If you keep it on a controller they are fine. I wouldn't trust them without a controller. If you don't have a controller just go with a jager or cobalt.
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