Best Ceramic Metal Halide Lights (CMH Grow Lights) For Growing Cannabis


The only disadvantage indoor WEED growers have over outdoor growers is the lack of natural light from the sun. However, this disadvantage does not deter indoor growers from getting the best out of their cannabis. Indoor weed looks healthier and it grows faster than that grown outdoors.

What you may consider a disadvantage is therefore an advantage. Indoor growers can control the growth of the crops by using nutrients, water and an effective lighting system. Grow lights are therefore a necessity for every indoor weed grower. There are different types of indoor grow lights that weed growers use for the different cycles of crop growth.

The most popular are LED grow lights, MH, COB and HPS grow lights that we have reviewed in some of our earlier articles. There is another kind of grow light, which is also as popular as LED, and HPS grow lights. These are CMH or Ceramic Metal Halide Grow Light.

Top Ceramic Metal Halide Grow Light- Comparison Chart

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Things you should know CMH grow light

Basic Things you should know about a CMH grow light

What is the CMH (Ceramic Metal Halide) grow lights?

Also known as, LEC or Light Emitting Ceramic, the popularity of CMH is catching up with any weed growers because of the efficiency of the light, which is especially good for crop photosynthesis. CMH grow lights also go by the name Ceramic Discharge Metal Halide (CDM), the lights use ceramic technology and they have the qualities of metal halide and HPS grow lights.

The lights use ceramic arc tubes very similar to the tubes in HPS grow lights. They also operate at much higher pressures than the quartz tubes glass tubes of metal halide grow lights. CMH grow lights, just like all other grow lights, come with their own advantages and disadvantages. Before we review some of the best CMH grow lights in the market and below are detailed buying guidelines for ten of them but before that, below are the reasons why you should switch to chm grow lights.

(Advantages/Pros?) Why should you start using/switch to CMH grow lights?

The grow lights competition is one of the stiffest for indoor weed growers. For you to get the best results out of your crops, you need to keep up with the latest technology and do away with the old. CMH is one of the latest grow light technologies taking the weed growing market by storm.

Before you decide on whether you want to change to this new technology and give your crops better service, it is good to understand what makes hem a popular choice for many growers and what the downsides are.

In short:

  • Better  PAR efficiency
  • Wide and finest Spectrum
  • Better CRI
  • Long- Lasting
  • Heat Consumption
  • Better Color Stability
  • More Efficient
  • Provide UV lights

Wide Spectrum

Another good reason for the popularity of the CMH grow lights is their full spectrum coverage, which is the finest in the market. This the light accomplishes due to the highly effective ceramic arc tube. The ceramic arc tube unlike other types of tubes can resist high temperatures. The lights also come with a well-balanced plectrum that spreads evenly across all the crops, touching every one of their spots.



Better PAR Efficiency

One of the reasons many growers are switching to CMH grow lights is due their excellent PAR efficiency, which is much better than that of many other types of grow lights. Other grow light models such as MH and HPS waste too much energy, which does not help with crop growth.

Better PAR Efficiency

Natural color rendering index

If we compare with other kind of grow lights then the CMH lights can provide us the highest measurement of natural Color Rendering Index (CRI). It shows us, how an object can be seen through human eyes and how well and elusively it can reveal the color shades. The higher number of CRI gives you a realistic view. If we rate sun light 100 CRI then a CHM grow light can produce 80-96 CRI. That’s why; it can show you the real view where the other lights will show you different type of colors like purple, blue or yellow.


Ceramic arc tubes have an advantage over other tubes and bulbs because they are resistant to heat and other problems. This makes the grow lights last longer than others without breaking down. The grow lights run for 24,000 hours, which is equal to running for a period of three years. For 20,000 hours, the grow light keeps a constant lighting and heat strength of 80%.

Heat Consumption

Despite running at high temperatures, CMH grow lights produce less heat compared to many other grow light models in the market. The bulbs of the grow lights do not burn the leaves of the crops and it is one of the best options to use in a grow room or a GROW TENT for a good yield from efficient growth.

Better Color Stability

CMH grow lights are consistent in their light and color dispensation. They do not lose their effectiveness or quality at any time throughout the growing cycles. Other lights lose their effectiveness after some time.


CMH lights are very efficient and the yield per watt from CMH grown crops is higher than that of many other grow lights. If you follow all the growing guidelines, you can have a yield of 20% more than, if you grew your crops under MH lights

Provides UV light

Besides offering full spectrum light, CMH grow lights also offer more UV lights than many other grow light models. Plants need UV lights for protection and proper growth. The light also helps during the vegetative stage and ensures that the crops grow with strong branches.

Downsides of Ceramic Metal Halide (CMH) grow lights (Cons/Disadvantages)

In short

  • Not best choice for flowering
  • Provides UV lights
  • Little Bit Expensive
  • Quite high Heat Output
  • It isn’t for all kind of ballast.


HPS grow lights are the best options to use for the flowering stage of your weed crop. This is because they provide more red spectrum than all other grow lights. CMH grow lights have a better-balanced light spectrum but they are not the best options for the flowering stage.


The grow lights provide UV A, UV B and UV C lights. Though the UV brightness of the grow lights provides the crops with enough protection and all they light they need for proper growth, they come with one disadvantage. UV C brightness may cause harm to the human’s naked eyes and it therefore important to wear protective eyeglasses and full-sleeved clothing while handling the lights.

Little Bit Expensive

Another disadvantage of the chm grow lights is that they are more expensive than many HPS grow lights in the market. Their processes are actually double that of HPS grow lights. They however save more energy and are more effective in light coverage. They also last longer, which makes them worth their high costs.

Quite High Heat Output

With over 700 nm lights, a chm is one of the highest heat-emitting bulbs.

Does not support all ballasts

The only ballast you can use with a CMH bulb is the magnetic ballast. You also can not place the bulbs in any other angle besides horizontally or straight up.

Things you should know before and after getting a CMH grow light

Do you know what is the most important and trickiest thing about a CHM light? It’s the ballast. Its quite tough to understand the specifics of CHM ballast that’s why, we recommend you to buy a entire CHM kit.

However, its much better to purchase a new one because CHM doesn’t work on so many type of electronic ballast for high frequency issue. The CHM bulb only supports on some good quality high end ballast with microprocessor. That’s why if you’re new with CHM technology then you should buy a full kit which is available with a fixture, bulb, reflector and everything in a package. It’s very easy to install and use.

An ideal CHM kit has square-wave technology ballast which will save you from EMI (ELECTROMAGNETIC INTERFERENCE) issues.

★★ Top 5 Best-Selling CMH Grow Lights on Amazon

Comparison of CMH and Other Grow Lights

CMH vs. MH

Some people assume that ceramic metal halide and metal halide are the same but they are completely different. They however share the same technology but their constructions are different. You cannot use a CMH bulb in MH ballast and vice versa, CMH has a better light spectrum and it runs cooler than a MH light. Lifespans for the MH bulb are also shorter than those of a CMH bulb. MH is also more affordable than CMH.

EfficientCheap in Price
Better Spectrum Not better spectrum than CMH
Lifetime of 24,000 hoursLifetime of 10,000 hours


CMH and HPS feature the same bulb technology but with very slight differences. When it comes to effectiveness, HPS are a notch higher than CMH. Most of the PAR light from HPS lights is provided by the red lights whereas CMH lights provide a more balanced PAR for the flowering and vegetative phases of growth.

What is the CMH grow lights

When it comes to efficiency, CMH are better than HPS lights and they have longer lifespans. Cost wise, HPS lights are more affordable than chm lights and they are better for the flowering phase.

More efficientBest for flowering stages
Balanced and better spectrum Quiet Cheap in price
More than 2x lifespan of HPS
9000 hours of lifespan


LED lights have more advantages over CMH lights in that they are more energy efficient and they produce very low heat. You can place LED lights near the crops without the fear of them overheating while you have to be more careful about the distance between CMH lights and the crops. LEDs also have longer operating times as compared to CMH lights but they are more expensive.

CMH lights on the other hand are more affordable and have lower usable life times as compared to LED lights. LED lights come in different categories and there are more products in the market with factual descriptions from their manufacturers than there are with CMH lights. LEDs also have a better light coverage and you can use them for all growing phases of the crop.

AffordableVery simply target any PAR range
Quite low useable lifespan than LED Lower heat consumption
Longer Running Time
Quite expensive

Which CMH grow light should you buy?

At first, do you really want to grow with CMH system?

Well, when you decided to start growing with a CMH system our advice is you should get a full CMH system. You also have to decide the budget.

If you’re confused and you don’t know which grow light you should purchase then stop worrying now! We have selected some best and budget-friendly system, bulbs and ballast reviews for you. Scroll down to read those reviews.

Best CMH Grow Light Systems

Grow Co. 630w Ceramic Metal Halide

Grow Co. 630w Ceramic Metal Halide is one of the most popular CMH lights in the market. It features highly efficient low frequency ballast with a hammer tone aluminium reflector. The light has a wide spectrum and a good cri that resembles natural light from the sun.

The lighting system is much better than that from many other lamps in the market. The PAR/Watt efficiency of the light is also of a much better quality, which gives the crops optimal lighting. The light comes with a two-year warranty and fully housed ballast housing. Included in the package is a 240V fifteen-foot power cord.

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Why it is a good buy

  • Has better cri than many other products in the market
  • Mimics the natural sunlight perfectly
  • Fully sealed ballast housing
  • Two-year warranty
  • Energy efficient
  • Reflector applications that allow the crops to get optimal light coverage


  • You have to buy the lamps separately


The above CMH grow light is affordable and it is great for the vegetative and flowering stages of plant growth. It has great reflective abilities unlike many other lights, which ensures that your crops get a good light coverage without any escaping out. I would recommend the light for new and professional weed growers.

Grow Co. 315W CMH System Grow Light Worth Your Money

If you are looking for a CMH grow light that is worth your money, go with grow co because the company never disappoints. It is one of the most quality and trusted brands in the market. Their 315-watt grow light is a favourite with any growers because it comes with several advantages.

The 315-watt grow light comes with a full spectrum Phillips CMH bulb. The 3100K bulb runs on 120 to 240 volts and comes with a 240 volts power cord. Besides the amazing and efficient lift spectrum, the grow light also comes with a warranty of two years. The heat production of the grow light is low and does not burn the crops.

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Why it is a good buy:

  • Has low heat dissipation
  • Energy efficient
  • Comes with a 240 volts power cord
  • Its low frequency ballast is specifically designed for CMH bulb technology
  • Comes with a two year warranty
  • Long lasting
  • Full spectrum lighting


  • The grow light is very bright and you require protection glasses because of the UV light
  • For those opting to use 120 volts, the light does not come with a 120v power cord
  • It has a slow restart, which is not a major problem for majority of the users
  • Does not come with a timer


Grow Co is a great company and you will not go wrong by buying any of their products. You get quality and efficiency from their grow light that will also save you great amounts of energy thus reducing your electricity bills.


Is the reflector surrounded with glass?

No, it’s not!

Is it energy efficient?

Obviously, it is.

Is that available with a timer?

No, it’s not available with a timer.

What is the coverage area of 315W CMH?

Covers up to 3×3 area.

Is it good for a greenhouse?

it’s good for greenhouse

VIVOSUN 98% Ultrahigh Reflectivity 315W CMH Grow Light  Best Reflectivity Guaranteed

VIVOSUN is a professional indoor growing and hydroponic manufacturer that provides growers with the most quality products. The above 315W CMH light is one of their best in the market and one of their first CMH lamps. The unit covers an area of 3×3, which ensures that you get a good yield out of your harvest from healthy looking crops.

It is ideal for both the vegetative and flowering stages and uses advanced low frequency square wave technology. The light comes with protection against overheating, short-circuiting, end of bulb and ignition failure. It uses a highly reflective Vega aluminium hood, which allows the plants to get optimal light coverage. It also comes with adjustable ballast features and a three-year warranty.


  • Reputable company, which many growers trust for quality and reliability
  • Ideal for vegetative and flowering stages
  • Efficient full spectrum light
  • Adjustable ballast features
  • Three-year warranty
  • Comes with a power cord


  • Expensive
  • Bulbs bought separately


Does it put-out heat?

Yes, it does.

Do I need to vent it?   

If your plants are in a bounded place then you need to vent properly.

Which bulb should I use in this fixture?      

Any 315w CHM bulb will work smoothly.

Does the light have any power (on/off) switch?

No, it doesn’t have any switch but it has removable cords.

How many bulbs should I use for preventing hotness?

One bulb.

VIVOSUN 315 Watt CMH Grow Light Fixture  Powerful with energy efficiency

Many of the weed growers must have at one time or the other bought one or many of their gardening tools and equipment from VIVOSUN. This is because it is one of the most prominent creators of quality weed gardening products. The 315-watt CMH grow light is an extremely great light for weed growth. The light comes with 98% ultra-high Italian Vega aluminium, which guarantees you more and better yields.

Being the newest model, this particular light has better and more intriguing arrangements. The ventilation system is better and the material that goes into making the light is of the highest quality. The light has low energy consumption abilities, comes with quality reflectors, and built-in ballast.


  • It is a modern version of the older VIVOSUN 315W CMH grow light
  • Has a better ventilation system
  • Good reflective rate
  • Low energy consumption
  • High quality Italian Vega aluminium material for more yields
  • Built-in-ballast


  • More expensive than the original model
  • Bulbs bought separately


The light is great for the vegetative and flowering stages of crop growth with better and more yields as compared to other CMH lights. Even though it is more expensive than the older model, it is worth the price and I would recommend it for your cannabis.


Does the fixture have built-in ballast?

Yes, it has.

How much volt does it use?

It uses 120v.

Does it come with a bulb and can I use any CMH bulb on it?

No, it doesn’t and yes you can use any CMH bulb.

How lights can be daisy-chained together?

As many as you want to use ?  

TopoGrow 315W CMH CDM Grow Light

TopoGrow 315W CMH delivers a light spectrum that is very close to the natural sunlight. It is better than hid systems when it comes to light discharge. The fact that it efficiently operates at higher temperatures, crops get more natural light, which in turn leads to higher, and more quality yields. The light covers an area of 4×4, which also ensures you get a larger harvest. For the flowering phase of the crop growth, the light helps with more bloom using the enhanced reds.

It is also as good for the vegetative stage as it is for the flowering stage. The light has a lifespan of 10,000 hours, which is much less than that of many other CMH lights. The package includes a reflector, a 315W ballast, lamp, a heavy duty 1/8 inches rope hanger, a power code and metal hooks.

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Why it is a good buy

  • Has low power consumption making it an energy efficiency lighting system
  • Good for both vegetative and flowering stages
  • Comes with a rope hanger
  • Has a reflector application
  • Affordable


  • Has a shorter lifespan compared to other lights in the market

Hydro Crunch CMH o2-315 Rope Ceramic Metal Halide

Crops need a good spread of lighting for them to grow healthy and yield much. The above 315W CMH grow light provides full spectrum light that allows your MARIJUANA to get optimal lighting during their vegetative and flowering stages. The light generates less heat than MIH and HPS lights.

The light closely matches that of natural sunlight meaning it is safe for the crops. Hydro crunch 315 w coverage areas is 3×3, which leads to higher harvests with low costs. The package comes with ballast, reflector, and an adjustable light ratchet hanger. The light also includes a daisy chainable feature with a two-year warranty on the ballast.

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Why it is a good buy

  • Comes with a two year ballast warranty
  • Full spectrum light
  • Energy efficiency
  • Affordable
  • Comes with a reflector
  • Comes with a ratchet hanger
  • Ideal for vegetative and flowering stages


There no bad things to say about this CMH light and it will do your crops great as well as save you n energy bills. I would recommend it for your weed growth.

All in One-Sun system LEC 315 light Emitting Ceramic Metal Halide 

The sun system CMH light bulb is far the most popular ceramic metal halide in the market with very few other bulbs coming close to match its quality. Though this makes it also more expensive than many other competing lights, it is worth the price. The light comes with everything your plants need for proper lighting.

It is easy to use too because all you need to do is plug it in and start to grow your weed. The light comes with an all in one reflector. It also contains the right ballast needed to power its lamp. The bulb hangs vertically and is lighter than horizontally hang bulbs. The reflective material is German aluminium with 98% reflection and the corners of the material are 95% reflective.

The highly reflective material ensures that your crops get light uniformity and optimal output without losing any light. The coverage area of the bulb is 4×4. It is ideal for the vegetative and flowering stages of the crop growth and it comes with a one-year warranty


  • Comes with an all in one construction making it more com-act than many other CMH lamps
  • Bulb hangs vertically which gives it a more light spread compared to horizontal bulbs
  • It has a long lifespan of 20,000 hours
  • Has a 315W Phillips bulb that comes with 33,000 lumen
  • Has low heat output
  • Comes with free ratchet hangers
  • Comes with reflective material that allows the crops to get optimal output and an even light distribution


  • It is more expensive than other competing CMH bulbs


Sun system is simply the best and worth spending money on if, you want to get the best out of your weed. I would highly recommend it.

Prism Lighting Science Ceramic Metal Halide : The Best and Most Versatile CMH Kits.

Shopping for a CMH light can be hard. Do you need it air cooled because you can’t cool your grow room? Do you need it to be low profile because you have low ceiling height? Are you looking to retrofit your old single ended reflector and save some money? Or do you just want the best equipment available to maximize yields? If you said yes to one of the questions above, then Prism Lighting Science has designed a CMH light package with you in mind.

The foundation of any CMH kit includes a high-quality ballast and superior CMH grow light. The Prism Lighting Science 120/240 Volt ballast has built-in ignition failure and thermal protection for your safety. They believe in the quality of this product and include a 3-Year Warranty from the date of purchase. All their packages also include both a 120 and 240 Volt power cable, mogul base socket adapter and the best CMH grow light on the market, either the 3100K or 4200K Philips lamp.

The most notable feature of this kit is the versatility. No one can beat the versatility of their packages as they offer many different reflector combinations. These include either a low profile Prism Wing Reflector, Sun System Neutron Reflector Hood, or Sun System LEC 315 RA Reflector. Or, you don’t even have to buy a reflector at all.  

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  • 3-Year Warranty

  • Comes with free mogul base socket adapter

  • Compatible with both 120 and 240 Volts

  • Many different buying options

  • Awesome customer service

  • Cheapest CMH bundle on the market.


  • Can get hot

  • Must use ventilation if in enclosed area.


Do I need Ventilation?

If in an enclosed area, ventilation is always recommended to reduce heat.

Does the ballast have an on/off switch?

The ballast does not come with an on/off switch.

How many bulbs can I use?

One bulb.

What voltage is the ballast compatible with?

The ballast is compatible with either 120 Volts or 240 Volts.

Will it work for both Veg and Flower?

They provide the option of either the 3100K (Flower) or 4200K (Veg) Philips bulbs.

Best CMH Grow Light Bulbs

Philips Master 3100K GreenPower CMH Light Bulb: Overall Best

When it comes to manufacturing quality products, not many companies can beat Phillips. The company sells all minds of bulbs including LEDs, HPS, CMH, MH and CFL among others. Many growers trust the brand because of the durability and quality of the products.

This particular CMH bulb comes with many benefits, which include a temperature of 3100 and a lumen of 33,000 outputs. After 8,000 hours of use, the bulb can retain about 33,000 lumen. The lifespan of the CMH bulb is 20,000 hours of natural light, which is sufficient for all the stages of growth.

The bulb is good for the flowering stage though it is also efficient for the vegetative stage. It uses low frequency ballast and an open rated lamp construction that reduces heat from the arc tube allowing it to emit less heat than MH and HPS bulbs.

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  • The bulb is from a reputable firm thus you can trust its quality and efficiency
  • It is durable
  • Has a long lifespan of 20,000 hours
  • Great for the flowering and vegetative stages
  • High lumen
  • Has a low heat output


  • It is more expensive than other competing CMH bulbs in the market.


If you do not mind the price and want to go with quality, then Phillips master will be the best option for you. You can trust the bulb to provide your crops with efficient lighting especially during their flowering phase.

Protopia CMH315W4K CMH Grow Bulb :Reliable

If you are on a tight budget and looking for an effective CMH grow light, buy Protopia ceramic metal halide growing lights. Compared to the other CMH lights, they are more affordable and with the same efficiency. Compared to Phillips, Protopia has more PARS out of its bulbs.

The 315-watt light bulb has 3000K and 37000 lumens with a rich full spectrum. The bulb uses low frequency ballast and comes with a phospar coating outside the arc tube, which adds to the rich light spectrum. The lights promote higher rates of metabolic crop activity and higher resin production through its powerful far-red spectra and UV lights.

It is best suited for the flowering and vegetative stages of weed growth. The CMH light also has a long life span of 15000 hours and comes with a one-year guarantee.

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  • Has one of the richest full spectrums
  • More PAR on its bulbs than many other HPS grow lights
  • Great UV light for production of more resin and metabolic activity
  • Long lasting
  • Comes with a one year warranty
  • Available in different wattages
  • Affordable


  • The bulb deteriorates faster than other models in the market
  • Has a much less CRI

Best CMH Ballasts

Expert Grower’s Choice: Phantom II E-ballast for 315W CMH Grow Light Bulb

Finally, it’s time for the last review. What did you decide? Are you going to buy a bundle or you want to do something different? Do you want make your own CHM light system? Do you have bulb and reflector but don’t have a ballast?

The phantom CMH 315 w grow light is one of a kind because unlike many other lights, you can operate it remotely. It uses low frequency square wave ballast specifically designed for its high intensity lamp. The lamp is suitable for both the vegetative and flowering stages of crop growth, the light features an internal RF shielding and a multi-aspect protection circuit.

It is also versatile and comes with 120, 208 and 240 input voltages. The lamp is silent, energy efficient and reliable. You can mount the lamp next to either a reflector or a few feet away using lamp cord extensions. The light comes with an 8-inch 120v power cord and a three-year warranty.

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  • The trade name is a trusted name in the industry
  • Comes with a long warranty of three years
  • Has a high quality performance
  • Uses the latest technology
  • You can control the lamp remotely
  • It is versatile
  • Suitable for both vegetative and flowering stages
  • Comes with instructions
  • High power CH provided


  • Compared to other lights, it is less durable


The phantom company provides quality and reliable products, so you can trust that this grow light will give you all the services you need. The long warranty is also a plus and the light comes with overheat protection which makes it safe for the crops. I would highly recommend it for every weed grower.

Related Post:


With the above extensive review of CMH lights, we hope that you will know what to look out for when you are thinking of the kind of lighting system you want for your grow room. The lights are energy efficient, they produce less heat per watt and their light spread is good.

They are most suitable for the flowering and vegetative stages of crop growth and their lifespans depend with the models and wattage. Some of the lights come with great a UV light, which protects your crops from any harm.

For more on INDOOR GROWING LIGHTS, read our earlier articles. if you have anything to add or a comment to make, we will be glad to read from you.

4.6/5 - (27 votes)

Bowden draws from over a decade of home growing experience as well as consulting for small-scale and hobbyist-level growers. He has written hundreds of articles, thought pieces, and tutorials about growing cannabis at home

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