Hydor THEO UL Heater

Regularly: $36.26
Today's savings: 15%
100 Watt


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Shipping weight = 1.00 lb.


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Product Summary:

The Hydor THEO Heaters provide the proper temperature needed to make your home aquarium flourish with the most advanced heating technology available. THEO heaters are designed with a peculiar cylindrical shape that renders them practically shatterproof. Fully submersible, THEO heaters function with the PTC (Positive Thermal Coefficient) heating element, a special polymer sheet silk screened with heating ink (like your car's windshield defroster), that enables them to run dry for a short time without damage. The unit comes complete with an easy to read temperature dial that make it the simplest, yet safest aquarium heater available. Can be used vertically or horizontally.
Size: Unit is 3/4" diameter x 8.9" long (100 Watts, Great for aquariums 14 – 26 gallons)
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Product Reviews by Customers

Rated 4 out of 5 by 3 reviewers.
Rated 2 out of 5 by not great This heater is easy to adjust and has a light to indicate when it is on, HOWEVER, the thermastat on this heater does NOT work. My chiller will kick on at 80* and this heater will still be running even though i have the heater thermastat turned all the way down to below 71*. I have heard this is only an issue with the 100w model, which is the one i have. Other than that, it is very durable and powerful (it has no problem competing with my 1/15HP chiller) February 20, 2011
Rated 5 out of 5 by Best Heater I have gone through so many heaters for my 55 gal. and this one is the BEST...I have the 400watt...it keeps the temp perfectly with no variation...I have my tank on an outside wall with no insulation...we have very cold winters...so, I would highly recommend this brand. I am ordering another for a 60 gal. we bought today. August 22, 2010
Rated 5 out of 5 by Great Heater This is a great heater! I have a 400 watt for my 150 gal tank. i thought that it wasnt going to be enough wattage but it works great! This heater is a very efficent one! February 6, 2009
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