Choosing the right reflector for your HID grow lights can almost double your growing area!
Reflectors divert upward traveling light from HID bulbs back down toward plants. There are many different types of reflectors, and I’d like to quickly compare the most useful ones. With this information any potential grower should be able to choose the reflector that suits both their needs and their budget.
Parabolic dome reflectors hang vertically and are popular in large vegetative growth and clone production rooms, usually with metal halide (MH) bulbs. They provide an even distribution of light to a large area, and are less intense than horizontal reflectors. A 400 watt metal halide bulb will adequately light a 3.5’ x 3.5’ area for vegetative plants with one of these reflectors.
Basic horizontal reflectors, such as the popular and affordable Econo-Wing, reflect light slightly unevenly because they are angular. These basic reflectors are widely used because of their low cost, light weight and versatility (the reflector can be bent by hand for a wider or narrower area).
Air cooled reflectors like these Sun System models are very popular in the Colorado medical marijuana grow warehouses right now. Most commonly used with 1000 watt HPS systems, air cooled reflectors are also called hoods because of their shape. Air cooled reflectors are completely enclosed; the reflective metal stops about 3-4” below the bulb, and a plate of glass makes up the bottom of the hood. The hood has two 4”, 6”, or 8” adapters on two sides to connect ventilation ducting. Air is constantly moved through the hood to cool the bulb and surrounding area.
Standard air cooled reflectors have a couple of interesting traits; the reflected field of light is much narrower than that of any other reflector listed here, reducing the overall usable growing area to a little less than that of a basic horizontal reflector. This seemingly negative effect is balanced by the fact that the light penetrates deeper into the canopy of the plants. More light reaches the inner leaves that do not receive much with other reflectors. Wide models of air cooled reflectors are sometimes preferred because they minimize these effects.
Adjustable double parabolic reflectors, such as Adjust-A-Wings, increase growing area by as much as 65%- 88%. These reflectors are much wider than most, and the smoothly curved parabolas reflect light much more evenly than the angular parabolas of the basic wing reflectors. Adjust-A-Wings are commonly sold with their own deflectors (see next paragraph), called Super-Spreaders.
Deflectors like the Equalizer are small reflective metal pieces with holes that can be attached to any horizontal bulb socket. These deflectors divert some of the most intense light from directly below the bulb to spread it evenly across the grow room. This helps avoid ‘hot spots’ directly beneath the bulb, which are both hotter and brighter than the plants would prefer, and adds light to the usually dimmer edges of the grow room.
Fellow growers, what are some of your favorite reflectors?
New to growing and have a question on what kind of reflector to use? Just drop a comment with your planned setup and I’ll provide some feedback.