Experiments with light - Dallas Ft Worth Aquatic Plant Club - Aquatic Plant Central

Go Back   Aquatic Plant Central > Local or Regional Clubs - (Click button on right to expand) > Dallas Ft Worth Aquatic Plant Club

Dallas Ft Worth Aquatic Plant Club A forum for the members of the DFWAPC.

Reply
 
LinkBack Thread Tools Display Modes
Old 01-10-2013, 10:53 PM   #1 (permalink)
Senior Member
 
Join Date: Jan 2004
Location: Dallas, TX
Posts: 4,116
iTrader Ratings: 24
iTrader Positive Rating: 100%
niko is a regular member
Default Experiments with light

So I got interested in experimenting with light that REALLY covers the wavelengths that are best for the photosynthesis (400-700 nm). I don't doubt that any strong bulb will grow plants just fine, but let's see what I find with a mix of crazy colored bulbs. I will mix the weird color bulbs with bulbs that have more green so the light looks natural.

For starters, here's a picture of how the spectrum of my favorite bulb (Giesmann Midday) looks like:


That spectrum provides very little light around 640-660 nm which is where the second peak for the photosynthesis is. But the light looks very pretty (because of the greens in it). Keep in mind that there is a view that red light is being absorbed by the water so aquatic plants don't really need it. That is why, by the way, ADA bulbs have blue (good for plants) and green (good for people's eyes) but not really red. Well, that is one reason to want to experiment with a true Full Spectrum light setup. But also there is another very interesting thing - there is a way to boost the photosynthesis by using a wavelength that we normally ignore. Read on.

Here's what bulbs I got:

Giesemann Aquablue: Got these to balance the weird colors of the next two bulbs. They have both blue and green in the spectrum. In real life the light doesn't really look that blue though. Side by side with a Giesemann Midday this bulb does look blue but something like 9000K, not too strong of a blue:




Korallen Zucht Fiji Purple: Got this one because of the broad coverage of the red spectrum. The bulb apparently gives out a horrible purple color. Must be mixed with at least 3 bluer bulbs, some folk say even 4. Note the red peak. Such high red peak is not found in any other fluorescent bulb. It is about 2 times higher than what the photosynthesis uses in the red area.




Giesemann Lagoon Blue:


Note the 700 nm peak. That's pretty rare to see. Apparently there is an interesting phenomenon with the area around 700 nm. If plants are exposed to both the blue/red light (the normal range that we consider good for the photosynthesis) AND ALSO exposed to light around 700 nm and higher there's a boost of the photosynthesis:


Besides the rare 700 nm peak this bulbs also has huge blue/green wavelengths. This produces light that supposedly looks like a green, clear tropical sea (turqoise):




So. I am interesed to see if I can manage to concoct a normal looking light from all these bulbs. Just in case I have two other bulbs that are mainly blue. From a small experiment I did the last few days I can see that a specialty grow LED light (containing only red and blue LEDs) seems to boost the photosynthesis (could not figure out if the boost was from the strong directed light or the spectrum). But the color of the light is horrendous. So the mixing of the light to achieve someting normal is important.

Also what I'm very interested in now is to get the club PAR meter. Since it measures the amount of light falling inside the range 400-700 nm I should have some huge PAR readings by combining all these bulbs.

One thing that is important to note is that having funky wavelengths and exotic bulbs will do nothing if the intensity is not good. I will be using these bulbs over a 30 gallon tank. 4x24W (96W total) or 5x24W if I have to should be strong.

Last edited by niko; 01-10-2013 at 11:09 PM..
niko is offline   Reply With Quote

Advertisement [Remove Advertisement]
Old 01-11-2013, 01:54 PM   #2 (permalink)
Senior Member
 
fishyjoe24's Avatar
 
Join Date: May 2010
Location: Plano, TX. (dallas/ft. worth)
Posts: 2,704
iTrader Ratings: 4
iTrader Positive Rating: 100%
fishyjoe24 is a regular member
Default Re: Experiments with light

interesting study.
fishyjoe24 is offline   Reply With Quote
Old 01-13-2013, 03:39 PM   #3 (permalink)
Senior Member
 
northtexasfossilguy's Avatar
 
Join Date: Mar 2009
Location: Arlington, Tx
Posts: 384
iTrader Ratings: 1
iTrader Positive Rating: 100%
northtexasfossilguy is a regular member
Default Re: Experiments with light

Niko, if you figure out how to make it that teal tropical white/ blue in T8 or T12s or T5s let me know! I want that for my large cichlid/ moss tank. Hey by the way, long time no see, good to see that you guys are still doing cool projects
northtexasfossilguy is offline   Reply With Quote
 
Old 01-13-2013, 04:00 PM   #4 (permalink)
Senior Member
 
Newt's Avatar
 
Join Date: Mar 2004
Location: between Here and There
Posts: 3,133
iTrader Ratings: 49
iTrader Positive Rating: 100%
Newt is a regular member
Default Re: Experiments with light

The Fiji Purple will need to be used with bulbs that have a lot of green not blue to make the visual color more pleasing. Many bulbs in the 5000K - 6700K range have lots of green. Just about any Coralife bulb will have lots of green.

400nm to 700nm is the human visual spectrum not photosynthetic. The middle of that range doesnt do much of anything for photosynthesis.



A university study in the Journal of Plant Physiology found that many plants subjected to infrared light causes photosynthesis to stop.

Last edited by Newt; 01-13-2013 at 06:16 PM.. Reason: added gif
Newt is offline   Reply With Quote
Old 01-13-2013, 06:00 PM   #5 (permalink)
Senior Member
 
fishyjoe24's Avatar
 
Join Date: May 2010
Location: Plano, TX. (dallas/ft. worth)
Posts: 2,704
iTrader Ratings: 4
iTrader Positive Rating: 100%
fishyjoe24 is a regular member
Default Re: Experiments with light

fiji purple with blue will do good for saltwater but will look weird with plants.
fishyjoe24 is offline   Reply With Quote
Old 01-13-2013, 06:43 PM   #6 (permalink)
Senior Member
 
Join Date: Jan 2004
Location: Dallas, TX
Posts: 4,116
iTrader Ratings: 24
iTrader Positive Rating: 100%
niko is a regular member
Default Re: Experiments with light

Ah! Nice suggestions. I didn't think about the obvious - red needs green to turn toward white. Well, thank goodness green is what a "pretty to the eye light is" and such bulbs won't be that hard to find. Thank you both for the advice!

My hope with buying all these bulbs is to have time to get the tank running and knowing well how it reacts to fertilzers, light period, etc. Then try to change the bulbs without changing anything else. And see if I can catch any differences. Not too scientific, but if you have a feel for the tank you will be able to catch the changes.

I don't expect some revolutionary findings. But I suspect that there will be interesting observations - like for example some plants REALLY love this or that bulb (wavelengths). This has to do with what Joey said in another thread - it is not only the PAR, but the PUR that matters (that part of the 350-750 nm spectrum that the plants actually use). Apparently different plants use different parts of the spectrum. So it will be interesting to use different bulbs and see what they do.

Now, keep in mind the spectrum graphs that we all find could be misleading. From what I understand the Fiji Purple has only one single graph and it may not be reliable. Beats me why Sylvania, the company that makes the Fiji Purple bulb or Korallen Zucht, the company that markets it are not more upfront about the spectrum. In any case - that casts a shadow of doubt on all other graphs I think. I just believe that they are close enough to what the light actually is. And as long as the bulbs come with consistent quality it should be all good for our hobby purposes.

FossilGuy,

Hi to you too. I remember you moved away a couple of years ago. I too hope to be able to get the amazing green color from that light. After what Newt and Joey said it looks like there will be some serious mixing of bulbs going on. At least the intensity should be good I guess, haha.
niko is offline   Reply With Quote
Old 01-13-2013, 08:07 PM   #7 (permalink)
Senior Member
 
Newt's Avatar
 
Join Date: Mar 2004
Location: between Here and There
Posts: 3,133
iTrader Ratings: 49
iTrader Positive Rating: 100%
Newt is a regular member
Default Re: Experiments with light

Quote:
Originally Posted by niko View Post
............Now, keep in mind the spectrum graphs that we all find could be misleading. From what I understand the Fiji Purple has only one single graph and it may not be reliable. Beats me why Sylvania, the company that makes the Fiji Purple bulb or Korallen Zucht, the company that markets it are not more upfront about the spectrum. In any case - that casts a shadow of doubt on all other graphs I think. I just believe that they are close enough to what the light actually is.............................................
Ain't that the truth. I was wondering that about that Giesemann Lagoon Blue bulb that had the 700+nm spike - is the red really that high in the nm range. What I find hard to believe about the Fiji is not the area the blue and red show up in but rather the strength of the emissions. Its fantastically powerful. Keep in mind that the Fiji spectral graph is a normalized spectral plot while the Giesemann Lagoon Blue is a relative energy spectral plot. Apples and oranges.

Yes, Sylvania does make the Fiji Purple. (Too bad I don't work there anymore. Those lab guys were very friendly.) In addition to the normalized plot of the Fiji there is the ATI comparison chart.


Keep in mind that Fiji won't appear that bright to you as it has little green and humans eyes aren't that sensitive to blue and red.

I know of a common T5HO bulb that has a good amount of green and I may have some in the cellar. Its a GE Starcoat 5000K.

Another point from a university study showed that blue light optimizes plant leaf development (makes for more compact and bushy) and red light stem elongation (can make plants long and gangly).

The shorter wavelength blue light penetrates water better and more quickly than red, which is slower and absorbed more quickly. Chlorophyll traps blue and red light and a photon of each provides the same photosynthetic energy to the plant but is more efficient with red light at 650 – 675nm. Blue is used at the same rate as red and it is more available for reasons mentioned above.

Last edited by Newt; 01-13-2013 at 08:47 PM..
Newt is offline   Reply With Quote
Old 01-14-2013, 03:33 AM   #8 (permalink)
Member
 
Join Date: Jan 2012
Posts: 37
iTrader Ratings: 0
dtang21 is a regular member
Default

Subscribed :thumbup:
dtang21 is offline   Reply With Quote
Old 01-14-2013, 10:05 AM   #9 (permalink)
Senior Member
 
Join Date: Jan 2004
Location: Dallas, TX
Posts: 4,116
iTrader Ratings: 24
iTrader Positive Rating: 100%
niko is a regular member
Default Re: Experiments with light

Newt,

Now is the time to explain what is "normalized spectral plot" and "relative energy spectral plot". That indeed sounds like an important distinction. Maybe that super high the red peak of the Fiji bulb is not something so off-the-wall as I think.

Also do you have any counter intuitive suggestions on how to test all these bulbs? My idea is to run just the Middays for starters until I get a feel for the tank. Then add one of the exotic bulbs and see what changes. Then swap exotic bulb 1 with exotic bulb 2 and see what happens. Then add both exotic 1+2. But there maybe a more reasonable way.

Also would it make a difference to run this or that exotic bulb longer than the other?
Or the judge the effect of the red spectrum in a shallower tank because of the issue with light penetration?
Should I try to always keep the wattage the same no matter what mix of bulbs I have (otherwise the increased intensity may result in better growth)?
niko is offline   Reply With Quote
Old 01-14-2013, 03:38 PM   #10 (permalink)
Senior Member
 
Newt's Avatar
 
Join Date: Mar 2004
Location: between Here and There
Posts: 3,133
iTrader Ratings: 49
iTrader Positive Rating: 100%
Newt is a regular member
Default Re: Experiments with light

Fluorescent bulbs marketed for aquaria are often more expensive and not necessarily better than generic versions. They are also not necessarily marketed correctly. Many bulbs offer spectral output graphs. However, many of these graphs are measured in relative power on the Y-axis rather than a known reference like watts per nanometer per 1000 lumens. All that 'relative power' lets you know is that 100% is the highest peak at a given nanometer and all other peaks are relative to this. So, don't be fooled by nomenclature and packaging (marketing hype).

The normalized plot of spectral power output is an apples to apples comparison of the amount of energy a bulb is outputting in Watts/nanometer per 1000 lumens. The Fiji has a 0.1 microeinstiens on both the blue and red peak. Compare this to a Sylvania GroLux Std T12, the red peaks at a little over 0.02.



In the normalized plots below the T8 Philips Aquarelle (one of the most powerful T8s) the red peaks at a little over 0.05.
The Fiji peak of red is twice the intensity.


So, back to Relative Power> the marketing dept. looks for the highest peak. That becomes 100% or 1.0 or similar. All other peaks are 'relative' to the highest peak. It does not let you know the intensity of the peaks.

Giesemann has not released their data. I even requested it. A spectrometer will give you the info you need so a normalized plot can be made. I will see if I can find a web based site on how to do a normalized plot.

I will give the test parameters some thought and post later.

Last edited by Newt; 01-14-2013 at 08:02 PM..
Newt is offline   Reply With Quote
Reply


Aquatic Plant Central > Local or Regional Clubs - (Click button on right to expand) > Dallas Ft Worth Aquatic Plant Club > Experiments with light

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -8. The time now is 01:46 AM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2021, vBulletin Solutions, Inc.

Search Engine Friendly URLs by vBSEO 3.6.1