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Hydor Theo Heater
Hydor Theo Heater
Hydor Theo Heater
Additional sizes may be available!
Additional sizes may be available!

Please Note: Return of electrical equipment for exchange or store credit is limited to 30 days from the date of purchase. Beyond 30 days, please contact the manufacturer for repair or replacement as covered by the manufacturer's warranty.

Returned products must be unopened and in the original packaging to receive full store credit. Products that have been opened, used, or lightly used, will incur a 15% processing fee. Upon receipt of the returned product, store credit will be applied, minus the processing fee.

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* Patented heating element automatically turns off if water level declines
* Easy temperature adjustment - knob clicks at every degree change
* Submersible heater with shatterproof glass resists breakage

Patented heating film and special shatterproof glass make this submersible heater virtually unbreakable. Theo switches itself off if the heater is not fully submersed - avoiding overheating and damage. Precise temperature knob clicks in 1°F increments, and an indicator lamp lets you know when it's on. Suction-cup clamps included. 5-1/2 ft. cord. UL-Listed.

Watts Length Aquarium Size
200 12" 26-53 gallons

  • Adjustment knob
  • Graduated scale
  • Setting indicator
  • Minimum water level line
  • Indicator lamp
  • Shatterproof glass

Patented Heating Technology
This submersible heater operates with PTC, a heating technology patented by Hydor. Its heating element is made of a special polymer that has been silk printed with special ink. The ink heats up with the passing of electric current, and the heat is transferred to the water. Its unique feature is that it is self-regulating. The heating element turns off automatically when the heater is not fully submersed in water (such as when performing water changes). This prevents overheating and breakage of the unit.

Safety Precautions

  1. Unplug all electrical appliances before making water changes or performing any maintenance.
  2. Use this heater indoors only.
  3. Check voltage to verify the one that's reported on the heater label corresponds to your electrical supply.
  4. Do no use if either the cable or the heater are damaged.
  5. Do not plug in when out of the water.
  6. Keep water at or above "Minimum Water Level" line.

Customer Testimonials

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