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.
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
Temperature range: 70-94 degrees Fahrenheit
Fits in rear filtration chambers
120V AC UL listed USA PLUG
Included 5-1/2 ft cord
Easy adjustment, knob clicks every degree!
8.9" Tall
14-26 gallons aquarium size
Fully submersible or semi submersible (shows water level line)