10,000K or 6700K or does it matter?

srozell

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Jan 24, 2005
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Do plants REALLY care whether or not they are being lit by a 10,000k or a 6,700k bulb?

I tried asking my plants, but my wife threatened to call the men in white jackets again if I didn't stop. :D
 

defdac

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Re: 10,000K or 6700K or does it matter?

No, the PAR can be the same (equal amount of photosynthetic active radiation). The PUR-efficiency (photosynthetic usable radiation) tends to be higher for 10K bulbs though, which doesn't really matter that much because you can always add another bulb/reflector if you don't mind the electricity bill.

This article I think explains very good what to look for in a bulb:
http://www.aquabotanic.com/lightcompare.htm
My own extended PUR-efficiency list:
http://www.defblog.se/permalink/1402.html
 

srozell

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Jan 24, 2005
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Re: 10,000K or 6700K or does it matter?

I suffered a couple of debilitating concussions this year that make it next to impossible to understand technical documents.

Those links look very informative, but I currently lack the ability to comprehend them.

Could someone simplify it for me a bit?
 

reiverix

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Jan 29, 2005
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Re: 10,000K or 6700K or does it matter?

The difference between 6700k and 10000k is more important to you than to your plants.

The plants like both just fine. The better color temperature is the one your eyes like best.
 

Simpte

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Feb 17, 2005
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Re: 10,000K or 6700K or does it matter?

random_alias said:
The difference between 6700k and 10000k is more important to you than to your plants.

The plants like both just fine. The better color temperature is the one your eyes like best.

What he said.......... :) K is only important to YOUR eyes.
 

shoggoth43

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Jan 15, 2009
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As Richard stated. Pick the color rendering you like best. 6700 K is blueish, 10000 K much bluer and typically a more reefy type application. Halogens and others tend to be more yellow in the 3-4000 K range. This only applies to bulbs that actually give a K value. Some like the AquaFlora types aren't really any kind of K value and just give a tonal value, i.e. "pink" and have spikes of color bands in them. I doubt the plants care all that much since we likely give them more overall light than they consistently get throughout the year in the wild. Clouds/trees/turbidity and all that.

-
S

Richard Heath;6966 said:
The difference between 6700k and 10000k is more important to you than to your plants.

The plants like both just fine. The better color temperature is the one your eyes like best.