To complete your system pick the bulb that best suits your needs. Metal halide
lamps are blue-orientated in the light spectrum and are best used as a primary
light source if little or no natural light is available. This type of lamp promotes
plant growth. Need a little extra? Pick one of the blue burning high Kelvin metal halide
lamps for that little extra blue light. If you need a MH lamp for budding or flowering
pick one of the high Kelvin red burning lamps.