600w Grolux Lamp Made by the lighting giant Sylvania, the Grolux is a high quality dual spectrum lamp that has been our best selling lamp for a long time. Compared to the PowerPlant Super HPS and other standard sodium lamps, the Grolux has more light output in the blue end of the spectrum. This broader range of light is great at promoting healthy vegetative growth and flowering. Although it’s still not as good as using a separate Metal Halide Lamp for vegetative growth, Grolux lamps provide a good middle ground for use throughout vegetative growth and flowering. The market leader in the UK, the Grolux has a patented arc tube that Sylvania claim delivers the highest photosynthetic efficiency of any lamp in the world. Another patented feature of the Grolux lamps is the wound ignition antenna; this ensures ultimate starting reliability throughout lamp life. Highly recommend. 600w - 90000 lumens Colour Temperature (K) 2050 Fitting: E40 Average Life: 10,000 hours. To maintain a high lumen output we recommend you change your lamps every 9-12 months. 3 month warranty (must keep original packaging)