Interest in a side-by-side spectrum vs growth experiment for chaeto/ATS/terrestrial?

widmer · 08/21/2014, 11:14 PM

I have gathered the LEDs and equipment to conduct an experiment that I have always wanted to. So I am checking with you all to see if it is something you would be interested in seeing as it develops:

Basically, the dogma states that plants grow best under red (660 nm) and blue (420 nm) light due to the absorption preferences of chlorophyll. There are lots of LED fixtures out there that capitalize on this, each with their own special blend of red/blue/etc LEDs. But while All of them claim to be the best, none of this is actually demonstrated with sound data that I've seen. Looking at a chlorophyll absorption spectra, the simple conclusion would be that we should channel all of our electricity into producing 660 nm light. But I suspect plant growth is more complex than that. In fact, my hypothesis is that it is more complex than only requiring 420 + 660 nm light. So I am geared up to run a growth efficacy experiment comparing 6 different combinations of the latest greatest LEDs (cool/warm = XML-L2, 420/630 = XPE, 660 = Rebel):

1. 660 - 660 - 660 - 420
2. 660 - 660 - 660 - cool
3. 630 - 630 - 630 - cool
4. warm - warm - warm - warm
5. cool - cool - cool - cool
6. 420 - 420 - 420 - warm

I will have these arrangements in identical isolated enclosures under completely identical conditions, growing something inside (lettuce? I haven't yet decided...), and will see which truly produces the best growth. I figure this would be directly applicable to growing chaeto/macro/ATS/etc, and I presume many of you are gardeners as well, which is why I'm posting here, to see if anyone would be interested in following along. If not, I won't bother posting it here as it develops. Any takers?

widmer · 08/23/2014, 09:13 AM

OK, 180 views and 2 people stating they would be interested in seeing this play out... I will take this experiment to another forum. To the two of you who voted yes, feel free to PM me in a few weeks for an update.

Happy reefing

Arrgh · 08/23/2014, 10:29 AM

Perhaps after that concludes you could look into the effectiveness of different spectrum at different times of day, as this will also likely cause differences.

Example:
Red all day
Blue all day
Blue 3hrs - red 3hrs -blue 3hrs

and so on.

widmer · 08/23/2014, 09:42 PM

That's an interesting concept - what exactly is the theory behind varying the spectrum throughout the day? Can you recommend any links?

salty joe · 08/24/2014, 07:16 AM

You're up to 7 people. I am definitely VERY interested in your experiment.

If you decide to go to another forum, any chance you could PM that link to me?

View Poll Results: What is your interest level in watching this experiment?
I am very interested, would enjoy following along!	8	66.67%
I am moderately interested.	2	16.67%
I could take it or leave it.	1	8.33%
I will now devote my life to inventing a time machine to get the last 2 minutes of my life back.	1	8.33%
Voters: 12. You may not vote on this poll

08/21/2014, 11:14 PM	#1
widmer Drug Enthusiast Join Date: Oct 2007 Location: Rochester, MN Posts: 2,958	Interest in a side-by-side spectrum vs growth experiment for chaeto/ATS/terrestrial? I have gathered the LEDs and equipment to conduct an experiment that I have always wanted to. So I am checking with you all to see if it is something you would be interested in seeing as it develops: Basically, the dogma states that plants grow best under red (660 nm) and blue (420 nm) light due to the absorption preferences of chlorophyll. There are lots of LED fixtures out there that capitalize on this, each with their own special blend of red/blue/etc LEDs. But while All of them claim to be the best, none of this is actually demonstrated with sound data that I've seen. Looking at a chlorophyll absorption spectra, the simple conclusion would be that we should channel all of our electricity into producing 660 nm light. But I suspect plant growth is more complex than that. In fact, my hypothesis is that it is more complex than only requiring 420 + 660 nm light. So I am geared up to run a growth efficacy experiment comparing 6 different combinations of the latest greatest LEDs (cool/warm = XML-L2, 420/630 = XPE, 660 = Rebel): 1. 660 - 660 - 660 - 420 2. 660 - 660 - 660 - cool 3. 630 - 630 - 630 - cool 4. warm - warm - warm - warm 5. cool - cool - cool - cool 6. 420 - 420 - 420 - warm I will have these arrangements in identical isolated enclosures under completely identical conditions, growing something inside (lettuce? I haven't yet decided...), and will see which truly produces the best growth. I figure this would be directly applicable to growing chaeto/macro/ATS/etc, and I presume many of you are gardeners as well, which is why I'm posting here, to see if anyone would be interested in following along. If not, I won't bother posting it here as it develops. Any takers? Last edited by widmer; 08/21/2014 at 11:24 PM.

08/24/2014, 07:16 AM	#5
salty joe Registered Member Join Date: Oct 2002 Location: medina, ohio Posts: 2,419	You're up to 7 people. I am definitely VERY interested in your experiment. If you decide to go to another forum, any chance you could PM that link to me? __________________ Time to roll the dice.

08/23/2014, 09:13 AM	#2
widmer Drug Enthusiast Join Date: Oct 2007 Location: Rochester, MN Posts: 2,958	OK, 180 views and 2 people stating they would be interested in seeing this play out... I will take this experiment to another forum. To the two of you who voted yes, feel free to PM me in a few weeks for an update. Happy reefing

08/23/2014, 10:29 AM	#3
Arrgh Moved On Join Date: Aug 2014 Posts: 92	Perhaps after that concludes you could look into the effectiveness of different spectrum at different times of day, as this will also likely cause differences. Example: Red all day Blue all day Blue 3hrs - red 3hrs -blue 3hrs and so on.

08/23/2014, 09:42 PM	#4
widmer Drug Enthusiast Join Date: Oct 2007 Location: Rochester, MN Posts: 2,958	That's an interesting concept - what exactly is the theory behind varying the spectrum throughout the day? Can you recommend any links?