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CDM Lights: The Easy Way to Get UVA & UVB


Want bigger, bushier healthier plants with fruits and flowers that look, smell and taste better? Expose them to a broader light spectrum with more UVA & UVB.


Want UVA & UVB? Get it on a budget with CDM lights.


What’s a CDM Grow Light?


Maxibright CDM Horizon Lighting System


CDM (Ceramic Discharge Metal Halide) grow lights are designed to be used alongside your HID lights to broaden your light spectrum.


Doing this improves plant health and yield quality.


Specifically, CDM lights are known to emit lots of UVA & UVB.


What are UVA & UVB?


UVA & UVB are both ultraviolet wavelengths of light that increase the production of terpenes, flavonoids, essential oils and even vitamin D.


Plants exposed to UVA & UVB:


• Are bushier with shorter intermodal spaces and more lateral branches

• Have a better flavour and aroma

• Produce a bigger yield

• Have greater medicinal properties and pest resistance

• Have more flowering sites

• Develop bigger root networks that support heavier crops


What CDM Lighting Systems are Available?


If growing on a budget, there's a 315 Watt Maxibright CDM Euro Lighting System.

For a better spread of light, choose a 315W Maxibright CDM Horizon Lighting System. You won't get any heat build ups - this thing comes with a Maxibright Horizon Reflector. It has double layered, open design that creates a cooling air stream. It's compact but wide angled, giving you a nice, even 1.2m x 2.4m beam angle. You can slot between two HID lights without trapping heat.


How do you Position a CDM Grow Light?


It’s simple to fit them into your existing layout.


Option 1: Simply slot 1 x CDM light between every 2 x 600W HID grow lights (if using a 942 CDM lamp).

CDM Set Up
CDM Set Up 2

Option 2: It’s possible to grow from start to finish under a 930 CDM lamp. The quality of yield vs. the power consumption makes this a great option for many growers.


If doing this, you’ll want to use a reflector with a square footprint (like a Northstar Reflector) in a square tent (like our BAY6 XL). You will also need a 315W Ballast and a CDM Lampholder.


How do they Connect to a Reflector?


CDM lamps don’t connect to a standard E40 reflector fitting. If you get a CDM lighting system like the Maxibright CDM Horizon, this isn't a problem because a CDM lampholder is inbuilt. If you want to use another reflector you can use a CDM lampholder to do this. Just remember it's not as reliable as using a CDM Lighting System.


If buying a CDM lighting system from us, a CDM lampholder is included. If buying a CDM lamp to use with an existing reflector & 315W ballast, you will need to buy it separately.

This post was posted in Equipment, Grow Lights, Growing Tips, Lighting, Product Spotlight



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