# Does COlor Temp have effects on plants?



## secretagent (Mar 13, 2004)

Does the k in the lower range have any effects on plants?


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## compulsion (Mar 2, 2004)

some say no, i personaly think it does effect the plants, but the amount it effects it based on the intensity of the output of the lamp.
if it didnt, then why do all the ones who insist it doesent allways use bulbs like the GE's and 6500k, 10000k etc etc .

but dont listen to me. im just a newb


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## 2la (Aug 18, 2002)

It does only inasmuch as it reflects the spectral output. To some degree, the more you waver from the 5000-10,000K range the less favorable the _spectrum_, but this is not always the case. There are many ways to obtain a 6500K rating, just as there are many ways to obtain an 18000K reading. Yet the latter is the rating for Power-Glo (and one other Hagen lamp, possibly the Aqua-Glo) and many have had successful setups using this lamp. In my estimation the reasons are two-fold: First, color rating really doesn't say much about spectral output, or at the very least you cannot confidently predict the spectrum of a bulb based on color rating, and second, lamp manufacturers sometimes seem to use voodoo magic to obtain their Kelvin readings.


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## glass-gardens.com (Apr 14, 2004)

The spectrum of a bulb is rated as a "color temperature". The scale is based on the light emitted from a black object as it is heated. When a bulb is rated at say 5000K, it means it's spectrum is equivalent to that which a black object (carbon) emits at 5000 degrees kelvin. Tropical noon day sun is approximately 5000K, up in North America it's closer to 6500K.

CRI (color rendering index) is a measure of the bulbs color rendering accuracy, the higher the number, the more accurate colors are rendered under a given light, which generally translates into the bulbs smoothness of output along all wavelengths of the visible spectrum.

here's a definitve article on lighting:

http://www.thekrib.com/Plants/phisio.html


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## 2la (Aug 18, 2002)

glass-gardens.com said:


> The spectrum of a bulb is rated as a "color temperature".


That's not correct, and that's a misconception I've been trying (unsuccessfully, it seems) to blow out of the water ever since I've been posting here way back when. Your technical definition involving the black body is correct, but the correlation with spectrum is not. _You cannot predict spectral emission by looking at the color temperature._ Color temperature merely gives an indication of the *overall appearance/hue* of the lamp, but it does not provide any definitive inidication of the spectrum whatsoever. This website shows a comparison of different bulbs. Notice how there are several 6500K-rated bulbs and several 5000K-rated ones, and that the spectral emission of each of bulb within those respective groups differs noticeably from those of other bulbs--hence the statement that there are many ways (spectra) to produce a particular color temperature. Notice even further that among the 5000K-rated lamps, overall color production varies from "yellowish" to "pinkish" to "creamy white"! Bottom line is that color temperature is an inconsistent indicator of anything at best, misleading parameter at worst.


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## compulsion (Mar 2, 2004)

lol, i allways sit here wondering what to put to these light posts... cant think this time.

what does actually matter when picking a bulb?


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## glass-gardens.com (Apr 14, 2004)

2la said:


> That's not correct, and that's a misconception I've been trying (unsuccessfully, it seems) to blow out of the water ever since I've been posting here way back when. Your technical definition involving the black body is correct, but the correlation with spectrum is not. _You cannot predict spectral emission by looking at the color temperature._ Color temperature merely gives an indication of the *overall appearance/hue* of the lamp, but it does not provide any definitive inidication of the spectrum whatsoever


I'm sorry I should have stated that better, color temperature is the measure of the combined out of all wavelengths emitted by a given bulk, but you are correct, it doesn't mean a 5000K bulb can't be red so to speak. CRI would be a better indication at least of the smoothness of the output across the visible wavelengths that combine to give the color temp.

That being said, it is a useful figure in so much as it will get you in the ballpark if natural sunlight is what your aiming for, but I agree there are other considerations as well for plant growth and discouraging algae growth.


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## Capt. (Mar 11, 2004)

I could get more technical involving spectrums and things but I won't.

However, Diana Walstead did a test with numerous fluorescent bulbs and got the best results with the cool white. Cool white bulbs are around 3500K I think, so it shows that the K really has very little influence.


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## glass-gardens.com (Apr 14, 2004)

Cool whites tend to the reddish/orange from what I can see, which I would think would be in line with conventional thinking, but I've also read in her musings that she thinks greens are the key, and in another she talks about cool white and vita lights. Amano shows a rpeference to greens as well, my bulbs tend to the green side as well with great reulsts, but I've seen tanks with predominat reds just as vibrant.

In the end analyisis, maybe it really just doesn't make all that much difference as long as the intensity is there.


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## secretagent (Mar 13, 2004)

Okey so The Color temp is the smoothness of the wavelength and you can grow plants with cool white bulbs but the wattage has to be up their? Awwahaahaahaa *messyroadkil laughs uncontrolubly evil*


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## glass-gardens.com (Apr 14, 2004)

Messyroadkil said:


> Okey so The Color temp is the smoothness of the wavelength and you can grow plants with cool white bulbs but the wattage has to be up their? Awwahaahaahaa *messyroadkil laughs uncontrolubly evil*


Seems as if you can put any bulb on any tank and start a debate :shock:


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## dogg76 (Jan 31, 2004)

so is more lumens better? or is the spectrum more important? i was thinking of getting ge p&a bulbs but they have less lumens than my 6500k daylight bulbs. but the p&a bulbs are supposed to have a spectrum high in blue and red.


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## glass-gardens.com (Apr 14, 2004)

dogg76 said:


> so is more lumens better? or is the spectrum more important? i was thinking of getting ge p&a bulbs but they have less lumens than my 6500k daylight bulbs. but the p&a bulbs are supposed to have a spectrum high in blue and red.


to an extent yes, but P&A bulbs usually have profound spikes in the red, at least in my personal experience, the output is such that it can encourage algae growth because the intensity is less than adequate for plants and more than sufficient for algae.

Algae is opportunistic, it will take what your plants can't use, be it light or nutrients and the #1 key in algae control is to give your plants more of what they can use most efficiently so they can out compete algae.


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## Capt. (Mar 11, 2004)

I disagree strongly with glass-gardens. I am using the Plant & Aquarium bulb now and am seeing very good plant growth. I use one plant and aquarium and one daylight deluxe bulb.

You are on the right track with spectrum and less worrying about lumens. Plant & Aquarium bulbs are designed to put out light for photosynthesizing of plants (growth).

However, if you only have room for one bulb I would stay with the daylight deluxe, simply because you will like the appearance better. The P&A by itself will make your tank look very pink, but if mixed with a higher K bulb it looks fine.


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## secretagent (Mar 13, 2004)

So I still havent understood if the color temp afects plant growth
?


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## glass-gardens.com (Apr 14, 2004)

Messyroadkil said:


> So I still havent understood if the color temp afects plant growth
> ?


After reading all this and doing some further research, I would say color temp itself does not, rather specific wavelengths needed by the plant are what's important and apparently those wavelengths can be present in numerous bulbs with a variety of color temperatures. The intensity is important as well simply because even if you have a bulb that provides the right wavelengths, unless they are intense enough for the plant to use, it won't do much good and you could end up giving the algae the advantage anyway.

Or it could be that there really isn't a single answer that covers everything.

In other words go buy the bulb of your choice, and make sure you have sufficient CO2 and if you're plants are pearling, don't sweat it, if not then add more lights or go to a stronger bulb.


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## dogg76 (Jan 31, 2004)

thanks capt., i was planning on using 2 P&A bulbs with 2 chromas, or do you think i would be better off using the 6500K ge daylight bulbs with them? sorryfor hijacking your post messy...


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## glass-gardens.com (Apr 14, 2004)

Capt. said:


> I disagree strongly with glass-gardens. I am using the Plant & Aquarium bulb now and am seeing very good plant growth. I use one plant and aquarium and one daylight deluxe bulb


But you miss you're own point, you're using a combination, not just a P&A bulb, so in effect you are changing the overall color temp and inherently, the composition of individual wavelengths. 

And I qualified my statement by adding that intensity is part of the equation. Two P&A bulbs are going to put out less light than the combination you are using currently. And if the intensity is not there, the algae will benefit more than the plants, especially if the light provides the specific wavelengths used most efficiently by algae. For your tank, you may have sufficient intensity so that the plants can out compete the algae, that may not be the case for a larger tank, especially a deeper one.

I currently run 6 40 watt bulbs (daylight deluxe) on my 75, I used the same combo on a 90 and it proved to be inadequate. I could add a P&A bulb, and I might get an overall boost in the red, but the overall intensity would be diminished and that would most likely negate any benefit of gaining more wavelength specific lighting.


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## Capt. (Mar 11, 2004)

glass-gardens.com said:


> Two P&A bulbs are going to put out less light than the combination you are using currently. For your tank, you may have sufficient intensity so that the plants can out compete the algae, that may not be the case for a larger tank, especially a deeper one.


The tank is 22" deep. Also there is not a whole lot of difference in intensity of usable plant light between these two bulbs. If you want a great site for bulb info and a very good chart of different bulbs check out http://www.aquabotanic.com/lightcompare.htm



dogg76 said:


> i was planning on using 2 P&A bulbs with 2 chromas, or do you think i would be better off using the 6500K ge daylight bulbs with them?


If it were me personally I would go with 3 Daylight Deluxe and a Plant & Aquarium. I think any combination of those will work pretty well though. I've never used the Chroma 50 but it ranks fairly well on the chart mentioned above. The Daylight Deluxe are very cheap that's why I said 3 of them, I try to keep this hobby as inexpensive as possible.


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## aviel (Nov 12, 2003)

Hi,

In my opinion the ultimate comparison spectrum wise would be the PUR. The PUR is the integration of the light intensity with the photosynthesis response over the whole spectrum of the bulb.

I encourage everyone to read Ivo Busko's light comparsion article here - 

http://www.aquabotanic.com/lightcompare.htm

If you have one bulb then you should look for the one with the highest PUR that you can afford.

If you have several bulbs then I believe you need to shoot for some with the highest blue PUR and some with the highest red PUR. In this article there's a table that compares various bulbs PUR, blue PUR and Red PUR.

In the blue PUR 36-40W category the winners are:

10,000K Aquarelle with 18.8 Blue PUR
5300K PLL950 with 15.5 Blue PUR
Triton with with 14.9 Blue PUR

The simple 6000K GE Daylight Dlx is rated 11.9 - so if we chop off the first lucky runner then you can see that the daylight is not significantly lagging behind and it's cheap. And the 6000K does give us a good hint that this one should compete on the Blue PUR category.

In the red PUR 36-40W category the winners are:

Sylvania Glu Lux with 15.5 red PUR
Perfecto with 12.6 red PUR
GE plant and aquarium with 12.0 PUR

The simple 3000K GE Warm White Dlx has 11.6 PUR which is really good!! And the 3000K does indicate that we are in the red PUR category.

Just for comparison - the notorious cool White has 8.6 blue PUR and 9.4 red PUR.

So conclusion:
- Simple DayLight/WarmWhites are OK & cheap bulbs.
- Kelvin does provide good first indication on the bulb's PUR characteristics.

Aviel.


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## 2la (Aug 18, 2002)

aviel said:


> So conclusion:
> - Kelvin does provide good first indication on the bulb's PUR characteristics.


I'm struggling mightily with this concept, to the point that I made a scatter chart plotting similar color temperatures with their respective PUR ratings and came up with the following, from which I'm thoroughly unable to determine any type of correlation:










How would you relate color temperature with Kelvin in these cases?


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## aviel (Nov 12, 2003)

Hey,

Thanks for taking the time to plot this thing. I believe you shall be able to see some good correlation if you draw on the vertical left the blue PUR and on the vertical right - the red PUR and scatter some blue and red points.

Thanks,

Aviel.


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## glass-gardens.com (Apr 14, 2004)

Capt. said:


> The tank is 22" deep. Also there is not a whole lot of difference in intensity of usable plant light between these two bulbs. If you want a great site for bulb info and a very good chart of different bulbs check out http://www.aquabotanic.com/lightcompare.htm


You have two bulbs over a 22" deep tank? I'm sorry but looking at the configurations the daylight deluxe come in, I don't see how you could even come close to having sufficient light with just two bulbs unless your plants typically grow in shadows.


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## Capt. (Mar 11, 2004)

Message edited due to inappropriate content - GDominy


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## secretagent (Mar 13, 2004)

Well I guess that means that the spectrum is in the some what right spot for undemanding plants to grow AND the PUR is what matters the most? Well all I was wondering next is if I was able to grow swords with a cf with a color temp of 2650k and it also says its a 50/60 on the web page. 2.6 wpg!! Would I be able to? THANKS 

MessyRoadKil

PS: forgot to add its 3200 lumens


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## glass-gardens.com (Apr 14, 2004)

Messyroadkil said:


> Well I guess that means that the spectrum is in the some what right spot for undemanding plants to grow AND the PUR is what matters the most? Well all I was wondering next is if I was able to grow swords with a cf with a color temp of 2650k and it also says its a 50/60 on the web page. 2.6 wpg!! Would I be able to? THANKS
> 
> MessyRoadKil
> 
> PS: forgot to add its 3200 lumens


At 2.6 watts per gallon, swords should do just fine as long as you have the other factors covered.

I re-read an article by Karen Randall earlier today, I apparently misread it before and what she was saying about color temp, it was in March or Aprils issue of AUSA I believe. You should check it out. She pretty much confirms the fact the color temp is more a matter of taste as long as you have red and and blue wave lengths to satisfy the two types of chlorophyl present in plants, although she does state that too much in the red wavelengths will lead to somewhat tall and thin growth.

She recommends using a combination of 5000K and actinic, assumedly for reds and blues. I stay more to the blues although in a thirty I'm using a combination of 5000K and 6500K for a total of 85 watts with 50 watts for the 6500K and 35 for the 5000K (2.8PG) with good result, but not as good as a 75 running all 6500K with a total of 240 watts (3.2WPG) but after reading all the comments here, I'm ready to accept that this is more because of the greater intensity in the 75, coupled with the fact that the 30 is actually taller by about 3".

I do know that neither tank showed good growth and some fairly annoying algae until I hit the 2WPG mark, even with CO2 running around 15PPM.


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## 2la (Aug 18, 2002)

aviel said:


> Hey,
> 
> Thanks for taking the time to plot this thing. I believe you shall be able to see some good correlation if you draw on the vertical left the blue PUR and on the vertical right - the red PUR and scatter some blue and red points.











Still don't quite see the relationship...


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## secretagent (Mar 13, 2004)

So I am hoping your talking about what else the swords need insted of light intensity!  Well Im really sorry Ive been a nusence Though


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## glass-gardens.com (Apr 14, 2004)

Messyroadkil said:


> So I am hoping your talking about what else the swords need insted of light intensity!  Well Im really sorry Ive been a nusence Though


Yep, I'd say you're good to go on lighting, CO2 and iron to the roots would be your next concern.


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## secretagent (Mar 13, 2004)

Cool Well Im good to go on the Fe and Co2 *HAPPY*


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## glass-gardens.com (Apr 14, 2004)

Messyroadkil said:


> Cool Well Im good to go on the Fe and Co2 *HAPPY*


yeah, happy, till you have two foot swords threating to attack you


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## aviel (Nov 12, 2003)

2la,

I don't quite see my winning bulbs in your graph. For example - where's the warm white - it should provide 3000K. There are no 3000K and 6000K bulbs as well. And there's no 10000K bulb like the first runner up. If you provide the right data then you should see that for the higher blue/red PURs the dots are concentrated near the 3000K and 6000-10000K.

Aviel.


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## 2la (Aug 18, 2002)

I sampled bulbs from 4000K to 5500K from the Aqua Botanic article because of their preponderance. I even left out metal halides from the equation in case their greater intensity and different spectral properties made any difference. Regardless of what the sample range is, I would expect that if color temperature were to be a good or even decent indicator of anything at all, we should be able to observe a relationship in these graphs, which we don't. This data is, in my estimation, every bit as "right"--if not more so--than sampling from the extremes. Otherwise the statement that "Kelvin does provide good first indication on the bulb's PUR characteristics" must be amended.


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## secretagent (Mar 13, 2004)

COOLIO I love to hear what I want and that would be that I can have swords in MY tank!! Happy


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## plant_geek (Jan 28, 2004)

Interesting discussion, much of it over my head but I'll jump into the fray.

In my world of indoor terrestrial gardening, the discussion on lighting, particularly flourescent, often focuses on somthing they call PAR, photosynthetic active radiation. Many feel this is the only true measure of a bulbs use to plants. Apparently it is next to impossible to get an accurate staement of the PAR from the manufacturers.

I've had really good luck with Tritons (one 15w on a 10 gallon is doing fine) and I strongly believe it's because of its intensity and PAR. I think these bulbs run around 10,000k but I could be wrong.

In indoor gardening we use MH (blue) for vegetative growth to promote stocky, green, robust growth. We then switch to HPS (yellow) for flowering. The differences in growth are amazing with the different lights. I think these same principles could be applied to aquatic plants. Bluer, higher k ratings should give stockier, leafier growth. Lower k might give leggier growth with more tendency for a plant to flower.


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## secretagent (Mar 13, 2004)

Thanks but Im still happy they WILL grow!


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## great_joe (Apr 25, 2004)

is 5300k enough for plants?


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## glass-gardens.com (Apr 14, 2004)

plant_geek said:


> Lower k might give leggier growth with more tendency for a plant to flower.


According to an article by Karen Randall I just read, lower K lighting, which would inherently have more red wavelengths, does just that.


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## plant_geek (Jan 28, 2004)

glass-gardens, do have a link to that article?

It could also be looked at like this (very general observation):

In the spring/summer, typically when most plants do the majority of growing, the sun is more directly overhead, emitting strong, bright blue light because of less atmosphere to pass thru.

In the fall, when many plants flower, the sun is lower in the sky, passing thru lots of atmosphere, resulting in red/yellow light.

Of course many plants may be day-length dependent for flowering so the wavelength may not apply, or it applies in a different way. I'm certainly not educated enough to go any further than this but in my experience wavelength does have an affect on plant growth.

I've noticed with aquatic plants the depth of cultural information leaves alot to be desired. Even the Tropica database seems slim on plant info. I want to know it's flowering tendencies, propagation techniques, sprouting techniques...on and on. Maybe since most are tropicals some of this doesn't apply, i.e. season of flowering, but still, can't they tell us more?


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## Wasserpest (Jun 12, 2003)

Interesting... most of the plants that I am familiar with flower in Spring and Summer...



plant_geek said:


> I've noticed with aquatic plants the depth of cultural information leaves alot to be desired. Even the Tropica database seems slim on plant info. I want to know it's flowering tendencies, propagation techniques, sprouting techniques...on and on. Maybe since most are tropicals some of this doesn't apply, i.e. season of flowering, but still, can't they tell us more?


There is quite a bit of information in Christel Kasselmann "Aquarium Plants", for example.


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## plant_geek (Jan 28, 2004)

Yeah, I knew this wouldn't come out right. I'm looking at this from a northern gardener's perspective, where day-length and strength of the sun have a huge effect on plants and flowering. Of course different plants flower during the entire growing season, some even outside of it.

The guy I got my aquatic plants from said alot of his flower during the spring also. I just snipped off a 2 1/2 ft flower spike from my ozelot sword. Is spring a typical time for tropical aquatics to flower, or is there alot of variability in flower times? Or, do they just flower whenever they want? Would a lower k light induce flowering?

Guess I bettter spring for that book. Thanks for the referral, Wasserpest.


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## glass-gardens.com (Apr 14, 2004)

plant_geek said:


> glass-gardens, do have a link to that article?


It was in the April issue of Aquarium Fish I believe.


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## 2la (Aug 18, 2002)

http://www.aquazoo.co.uk/page.cfm/type=Plants/PageID=72


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## glass-gardens.com (Apr 14, 2004)

2la said:


> http://www.aquazoo.co.uk/page.cfm/type=Plants/PageID=72


Not the article at all actually


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## 2la (Aug 18, 2002)

I know, but did you need that _specific_ article? I'm just trying to help your case, guy... :?


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## glass-gardens.com (Apr 14, 2004)

2la said:


> I know, but did you need that _specific_ article? I'm just trying to help your case, guy... :?


The article I referenced talked about lower color temp lights, plant and aquarium bulbs specifically I believe, didn't mean to come off rude, just that I was referring to a specific topic in the article


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## xjia (Mar 11, 2007)

as far as i know,colour temp effects on how your tank looks.
If you want to grow plants,you should check light spectrum ,blue and red.


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## tropicalfish (Mar 29, 2007)

You just dug up a 2 year old thread.


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## Tdon1md (Jun 3, 2007)

Capt. said:


> I disagree strongly with glass-gardens. I am using the Plant & Aquarium bulb now and am seeing very good plant growth. I use one plant and aquarium and one daylight deluxe bulb.
> 
> You are on the right track with spectrum and less worrying about lumens. Plant & Aquarium bulbs are designed to put out light for photosynthesizing of plants (growth).
> 
> However, if you only have room for one bulb I would stay with the daylight deluxe, simply because you will like the appearance better. The P&A by itself will make your tank look very pink, but if mixed with a higher K bulb it looks fine.


Ok, stupid question time again. If I wanted to duplicate your set up w/ my diy hood and 4 36" flourecent bulbs, what would I buy and where would I get it? I don't recagnize Pland& Aquarium blub nor Daylight Deluxe. I have a feeling I've overspent needlessly in buying "Aquarium" bulbs from LFS and online aquarium dealers. I supose what I really need is "lighting for dummies 101" cuz almost all of this thread is over my head. Would appreciate any help you can give. Not opposed to reading for myself but all articles I've found sounded very very much like the language used in this thread and again, way way over my head. I can't apply it if I don't comprehend the explination.

Thanks,
________
StylePepper


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## crazy loaches (Sep 29, 2006)

tropicalfish said:


> You just dug up a 2 year old thread.


Actually its 3 years old and a few months...


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## drtechno (Sep 2, 2007)

just use some sense, a combination of fullspectrum white and "show and grow" or "plantlight" or "aquarium" that has a purple-red light to it is fine.

you'll find out that you'll have algea problems if you go beyond 3w/gal or use alot those "snake oil 9999999K lights"; specially with co2.

..and you shouldn't have to have more than two flourescent light bulbs in a 30 gal setup anyways unless you keep your water dark brown from too much peat extract (dark water snake oil).


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## crazy loaches (Sep 29, 2006)

Tdon1md said:


> Ok, stupid question time again. If I wanted to duplicate your set up w/ my diy hood...


Oh and by the way Todd, the Capt hasnt been with us since Jan '05 so asking him questions here is probably pointless :wink:


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## dogg76 (Jan 31, 2004)

I have used the GE daylight bulbs(6500k) with the Ge Plant & aquarium bulb and didn't have any problems growing plants, I use the Coralife 4x65w fixture now. Man, this thread was old!


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## Tdon1md (Jun 3, 2007)

drtechno said:


> ..and you shouldn't have to have more than two fluorescent light bulbs in a 30 gal setup anyways unless you keep your water dark brown from too much peat extract (dark water snake oil).



Two bulbs @ 25 Watt each is 1.66 wpg. I'm new but that seems low. Everything I've read tells me that a 30g tank is right in the sweet spot of the 2-3 wpg rule of thumb. Am is mis-interpreting what I'm reading? What I think I'm starting to understand is that color spectrum is more important then K rating? Am I getting close? If so, then how do I get color spectrum when the only specs given are K rating and wattage?
________
Colorado medical marijuana dispensaries


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## crazy loaches (Sep 29, 2006)

Tdon1md said:


> Two bulbs @ 25 Watt each is 1.66 wpg. I'm new but that seems low. Everything I've read tells me that a 30g tank is right in the sweet spot of the 2-3 wpg rule of thumb. Am is mis-interpreting what I'm reading? What I think I'm starting to understand is that color spectrum is more important then K rating? Am I getting close? If so, then how do I get color spectrum when the only specs given are K rating and wattage?


Yeah I'd go with 2 lights for sure. Assuming you have them rigged seperately you can always go more than you need (even 3 or 4 total) and then just use however many your comfartable with. If you find you want to try more than just start turning on the extra one(s) for a midday burn for a couple hours and go from there. It all depends on your balance (co2, ferts, plant growth...).

As far as spectrum vs K then yeah if you have access to the actual spectrum then thats what I would go by. The same K value can have a multitude of different spectrums that produce the same number. Think of K as an average where the individual variables can vary drastically but the average is the same (like average 0 and 10, or 4 and 6, you get 5 for both). The problem is spectrum data isnt typcially provided and the few that are provided are probably not accurate enough to be meaningful. Like I said before there are some hobbyists like Sanjay Joshi that has measured and posted data for MH. Not sure if this has been done with fluoros. You can also use PAR data or PPFD which I think is photosynthetic photon flux density, but again these are rarely given. They do make meters though you can buy, Tom seems to like actually measuring light levels and adjust accordingly. So this isnt very easy. But an easy way is to check what others use. Take a look through the galleries and often times on beautiful tanks the specs are given. But in the end, most lights will grow plants! I think people often worry much more than they should. What I try is to provide either midday ~6500k lighting or several bulbs of varying types. For example in my current project I will have Giesemann 6000K midday and 11000K aqua blue plus, as well as GE Starcoat 6500K and UVL 10,000K Aquasun bulbs. I dont have the tank setup yet but the lighting is a nice blend of colors... The aquablue is of course blue, aquasun is redish, midday is yellowish-white, and starcoat greenish-white. Cant wait to see how the plants like the spread.


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## dogg76 (Jan 31, 2004)

The K rating is the color spectrum...3000k would be very yellow while 6500k would be more of a bluish white. As far as how many bulbs you use on your tank I think it is entirely up to you..

Crazy Loaches beat me to it and provided a better answer....


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## Tdon1md (Jun 3, 2007)

Ok, so here's what I'm thinking. Current USA makes a CF 36" hood w/ fan and 1 lunar light. The CF is 96 Watt. It comes w/ 10,000K / 420 (I think) Actinic. I'm going to swap out the factory bulb and go with their "dual daylight" 6700/10,000K. That's 3 wpg roughly, I'm automating pressurized CO2 w/ pH sensor and going to shoot for 30-35 ppm and dose EI kinda sorta (testing NO3 and Phosphate 2 or 3 times per week to make sure I'm on track). Any other ideas?
________
Problems with prilosec


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## epicfish (Sep 11, 2006)

dogg76 said:


> The K rating is the color spectrum...3000k would be very yellow while 6500k would be more of a bluish white. As far as how many bulbs you use on your tank I think it is entirely up to you..
> 
> Crazy Loaches beat me to it and provided a better answer....


3000K is very yellow pee. 6700K is regular pee. 10KK is crisp white, 14KK is bluish-white.



Tdon1md said:


> Ok, so here's what I'm thinking. Current USA makes a CF 36" hood w/ fan and 1 lunar light. The CF is 96 Watt. It comes w/ 10,000K / 420 (I think) Actinic. I'm going to swap out the factory bulb and go with their "dual daylight" 6700/10,000K. That's 3 wpg roughly, I'm automating pressurized CO2 w/ pH sensor and going to shoot for 30-35 ppm and dose EI kinda sorta (testing NO3 and Phosphate 2 or 3 times per week to make sure I'm on track). Any other ideas?


No, sounds good as far as lighting goes. Make sure you plant densely when you start out or else you'll fight algae, despite your pressurized CO2 injection.


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## dogg76 (Jan 31, 2004)

"3000K is very yellow pee. 6700K is regular pee. 10KK is crisp white, 14KK is bluish-white." 

I stand corrected...LOL


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## epicfish (Sep 11, 2006)

dogg76 said:


> "3000K is very yellow pee. 6700K is regular pee. 10KK is crisp white, 14KK is bluish-white."
> 
> I stand corrected...LOL



=P

I always thought 10K was bluish white until I started with reefing and realized that 10K was just a very crisp white.


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## eyebeatbadgers (Aug 6, 2007)

epicfish said:


> 6700K is regular pee.


Relative to how much you drink.:smile:


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## dogg76 (Jan 31, 2004)

When I replace my bulbs I am gonna try a couple 10k bulbs. I currently have all 6700k bulbs at the moment...


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## crazy loaches (Sep 29, 2006)

Tdon1md said:


> Ok, so here's what I'm thinking. Current USA makes a CF 36" hood w/ fan and 1 lunar light. The CF is 96 Watt. It comes w/ 10,000K / 420 (I think) Actinic. I'm going to swap out the factory bulb and go with their "dual daylight" 6700/10,000K. That's 3 wpg roughly, I'm automating pressurized CO2 w/ pH sensor and going to shoot for 30-35 ppm and dose EI kinda sorta (testing NO3 and Phosphate 2 or 3 times per week to make sure I'm on track). Any other ideas?


Sounds like that will work well for you. Just remember with 1 bulb you dont have any flexability on lighting (not a big deal, just nice to have). The 6700/10K options sounds good and I think some folks have liked the Current brand bulbs though I have no experience with them.


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## crazy loaches (Sep 29, 2006)

epicfish said:


> 3000K is very yellow pee. 6700K is regular pee. 10KK is crisp white, 14KK is bluish-white.





epicfish said:


> =P
> 
> I always thought 10K was bluish white until I started with reefing and realized that 10K was just a very crisp white.


Another reason the K values arent good to go by. Actually light around ~6000K should not be yellowish like many say, should be crisp white and should be just starting to be blue just a bit higher. But K values are just an approximation the manufacturers slap on the bulbs. Sanjay's testing revealed many lamps that measured several thousand K lower than what they were sold as.









From http://www.techmind.org/colour/coltemp.html


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## Carissa (Aug 19, 2007)

I have one 10,000k and one 4100k bulb on my 32g. I found that my sunset Hygro only gets the nice red tone if it's under the 10,000k bulb. Some of my regular hygro is getting a reddish tone on the leaves closest to the 10,000k bulb too. I don't know enough about it to explain why. My anubias are doing really well under the 4100k bulb, sprouting new leaves every week.


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