Showdown: CFL vs. High Intensity Cool Tube – Which is the Better Grow Light?

The main reason you are interested in growing your own is most likely because you want to grow a particular variety or strain of crop OR you want to create your own hybrid to suit your own tastes.  It certainly isn’t for convenience or immediacy.  From a practical standpoint, this probably means you are not going to spend a ton of time pruning and manicuring your crop—instead you are more likely to plant, feed, harvest, consume.

There are three main ingredients to a successful harvest.

  1. The variety or strain you are growing
  2. The nutrients you are using
  3. The lights you are using

This article is a summary of my experiences the last four years of growing using CFL lights and High Intensity lights.  It is by no means a proper scientific test but the results should still provide you with some value.

I did not include LED lighting in this comparison for several reasons.  Two years ago I tried an LED system (admittedly, this was early days for LED lighting) and found it ran with a lot of noise and put out a significant amount of heat—it was noisier than the Cool Tube and hotter than the CFLs.   I will eventually re-try LED lighting but am going to wait at least another year before doing so.

CFL Lighting

Grow Light Close up webAt first glance, CFL lights are an attractive option.  They have a long bulb life and are inexpensive at first glance.  My setup used 4 @ 85 watts and 2 @ 105 watts.  However, when you realize you need one set of bulbs for the veg cycle and one set of bulbs for the bloom cycle you realize that CFL bulbs are actually more expensive than the two High Intensity bulbs you need for these cycles.

Other advantages of CFL lighting include they are quiet.  Unlike High Intensity bulbs which often come with a cooling fan built into the lighting assembly, CFL bulbs are silent.  Another advantage of using multiple CFL bulbs is that it is really easy to hang different bulbs at different heights to make sure that all areas of your grow receive light.

Cool Tube High Intensity Lighting           

cool-tube-03I chose the 400 watt Cool Tube high intensity light kit.  This comes with an inline cooling fan and two bulbs, one high pressure sodium and one metal halide for use in the veg and bloom cycles.  At under $200 complete it gives CFL lighting a run for its money in terms of total price you pay for lighting.  In theory, CFL bulbs will outlast high intensity bulbs but I can’t attest to that as after 15 growing seasons both CFL and HI are going strong.  The inline cooling fan does put out some noise making a stealth grow unlikely.

One advantage of the Cool Tube high intensity light kit is that it really does run cool.  It adds less than 1 degree to the ambient temperature of the room which is a lot better than the 5 degrees CFL lighting adds.  During the summer months this can be an important consideration as I lost one CFL grow to heat stroke.

Another advantage is the Cool Tube is actually less expensive to operate than the CFL lights.  This is probably due to the digital ballast that comes with the Cool Tube…in any event, CFL lighting cost me about $31 a month to run, the Cool Tube was just over $25 a month to run.  Your mileage may vary.

Conclusion (and the most important difference)

While admittedly not the most scientific of tests, there is no way I’m going back to CFL lighting.  My reason actually has little to do with the above comments and all to do with the quality of the harvest.  Hands down, the Cool Tube produced more yield and better quality.  At the end of the day, isn’t that what matters?


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