The Eheim Heater is an ultra modern electronic thermal device for heating your aquarium. – Temperature can be precisely adjusted from 18deg to 34deg C and recalibrated if required. The control accuracy is +/- 0.5deg C. – Heat is kept at a constant level. The heating function is indicated by a control lamp. – Fully submersible. – Protected against dry running. – Laboratory quality glass jacket enlarges heating surface and ensures optimum even heat emission. – Suitable for Freshwater or Marine water. – Includes suction cup holder. – 200w heater suitable for 300-400l aquariums. – 406mm length x 36mm diameter. -250w heater suitable for 400-600l aquariums. – 452mm length x 36mm diameter. – 300w heater suitable for 600-1000l aquariums. – 506mm length x 36mm diameter.