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Hydor Theo Aquarium Heater 200W£10.57
Provide your tank with the proper temperature with the most advanced heating technology available. Hydor THEO heaters are designed with a peculiar cylindrical shape that renders them virtually shatterproof. Fully submersible, Hydor 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.
With an easy to read temperature dial, these heaters are the simplest, yet safest available. Ideal when placed in the vertical position but can be installed in a horizontal position completely submersed.