Choose between 3100k or 4200k light spectrum bulbs.
Ceramic Metal Halide are more expensive than standard HPS or MH lights, but they last about twice as long as High Pressure Sodium or Metal Halide lights, are more efficient watt per watt and create a more balanced light spectrum.
Advantages of CMH Lights
Better PAR Efficiency: A 630W CMH is about equivalent to a 1000W HPS. CMH lights have a more balanced colour spectrum that wastes less energy than HPS or MH lights producing light that is not used efficiently by plants. Per watt used CMH lights have create a higher Photosynthetically Active Radiation (PAR) rating which leads to a great yield per watt.
Realistic natural lighting: The CRI (colour rendering index) of a light how well a light shows an object (or plants) true colour to the natural eye. CMH lights have a high CRI that gives your grow area a natural look and lets you see the true colour of your plants. Unlike HPS lights that give a yellow glow and many LEDs which give a red coloured light.
Longer lasting: The Ceramic arc tubes in CMH bulbs are more resistant to breakdown, so they last longer then HPS and MH bulbs. CMH bulbs are normally rated at 20,000 hours where HPS and HM bulbs are rated for 10,000
Heat output: CMH lights are still High Intensity Discharge bulbs that product a significant amount of heat and require good ventilation, however they are more efficient and run cooler than MH and HPS bulbs.