This site is supported by the advertisements on it, please disable your AdBlocker so we can continue to provide you with the quality content you expect.
  1. We are after as many aquarium plant images that we can get, doing so will assist us in completing the aquarium plant database.

    https://barrreport.com/threads/aquatic-plant-images-wanted.14374/
    Dismiss Notice

I'm still not sold that light and color temp doesn't make a difference....sell me.

Discussion in 'Lighting' started by ShadowMac, Aug 23, 2012.

  1. ShadowMac

    ShadowMac Lifetime Members
    Lifetime Member

    Joined:
    Mar 25, 2010
    Messages:
    1,043
    Likes Received:
    13
    Local Time:
    8:44 PM
    I have read from a lot of people that all bulbs are essentially created equal, or close enough to not worry. I've read that light intensity does not impact color. However, my observations while in this hobby have seemed to be counter to this.

    Observation #1: Limnophilia hippuroides was much more colorful in tank A than tank B. Tank A had 2x24 watt T5's flora tube and daylight tube; 20 gallons. Tank B had two T5's 24 watt same tubes tank was 37 gallons. Both pressurized Co2. Visible difference in the color even under same light out of the tank when compared. (I meant to take a picture of this at the time, but never did.) I understand Co2 may have varied between tanks...but given healthy growth in both it should have been adequate for color development.

    Observation #2: Tank B(2) 2 daylight bulbs. Rotala Macandra "green" ....greener than previously in tank B(1) which ran 4 daylight bulbs. Same tank, same CO2 system. I have only achieved the beautiful coloration rotala macandra green is capable of when running the 4 bulbs. Observation 3 also shows this....

    Observation #3: 30c 7.5 gallon tank, running cheaper LED's that provided decent growth and some coloration in Rotala Singapore and a little in Rotala macandra "green". Recently switched to an ADA Aquasky (cool light for a cube btw). This light is much brighter and I saw an immediate increase in pearling. After One week dramatic improvement in color. The singapore gained some pink hues as well as the macandra "green". Same Co2 system...same bubble rate even. Same tank same routine. The only thing that changed was the light. Both adequate for growth...the Aquasky is more intense and the color is much closer to daylight. My T5 tubes look a little yellow when compared to the light of the Aquasky.


    A couple explanations I have thought of....light intensity does matter, duration of exposure to high light ie tips that run along the surface tend to get more color, proximity to the light source (which in a way is intensity as well). Is there a "quality" of light we should consider not just spectrum or intensity? UV rays? something? I'm just throwing out thoughts.
     
    #1 ShadowMac, Aug 23, 2012
    Last edited by a moderator: Aug 23, 2012
  2. Gerryd

    Gerryd Plant Guru Team
    Lifetime Member

    Joined:
    Sep 23, 2007
    Messages:
    5,624
    Likes Received:
    20
    Local Time:
    8:44 PM
    Well, the temp or Kelvin rating is not the same as intensity.....

    Are you running say 6500k on one tank and 14k on another?
     
  3. ShadowMac

    ShadowMac Lifetime Members
    Lifetime Member

    Joined:
    Mar 25, 2010
    Messages:
    1,043
    Likes Received:
    13
    Local Time:
    8:44 PM
    All daylight bulbs have 6500K. The last observation is the only tank that is running.

    I understand that kelvin rating is not the same as intensity, but I "feel" there is something we are missing about our light sources in regards to how plants respond.
     
  4. Tom Barr

    Tom Barr Founder
    Staff Member Administrator

    Joined:
    Jan 23, 2005
    Messages:
    18,694
    Likes Received:
    728
    Local Time:
    8:44 PM
    I get different plant responses and coloration from different bulb types.

    I've tried about 20 different brands and types of T5 bulbs.

    You have 2 things going on:
    1. Your perception of the reflected light(eg, a red color bulb will reflect more red light obviously........)
    2. True color and plant responses.


    You can simply try and see, but there is no hard fast rule about this.
    See what colors you personally like.
     
  5. Yo-han

    Yo-han Guru Class Expert

    Joined:
    Feb 6, 2011
    Messages:
    285
    Likes Received:
    0
    Local Time:
    8:44 PM
    By doubling the amount of light, plants usual not grow twice as fast but more like 50% faster. This is because they are not able to process all the light and in a response they turn red, so they no longer receive light from the red spectrum. Now they only receive blue light because chlorophyll is only sensitive for blue and red light, green light is neglected in green and red plants.

    Wavelengths chlorophyll is sensitive to:
    [​IMG]

    More light does make plants redder. About color temp (kelvin) plants don't care. Plants want PAR and this usual isn't cited on the package, so bulb A 6500K can have double the PAR output compared to bulb B. When bulbs have the same PAR output but different kelvin ratings like 3000K vs 14.000K (yellow/red vs blue), the only difference I (and others) noticed is you get more compacted 'bushier' growth with high kelvin and plants reach more to the light and become 'leggy' with red/yellow light. Hopefully this is useful for you!
     
  6. Tom Barr

    Tom Barr Founder
    Staff Member Administrator

    Joined:
    Jan 23, 2005
    Messages:
    18,694
    Likes Received:
    728
    Local Time:
    8:44 PM
    I've never found any truth to more compact growth and color temps/blue vs red in aquatic submersed plants.

    If I have more bulbs and angles of spread and light striking the leaves, then I will have more compact growth.
    But this typically means I also have more intensity with a wider and more bulbs in the fixture. If I have a dimmable fixture with a wide spread, then I can test and see if this is the case. Near as I can tell or see, that is not the case with aquatic plants.

    While you posted the Chl a response, Chl b is slightly different and then there are many many accessory pigments that catch and funnel light energy into the light harvesting centers.
    So plants can adapt and use pretty much most color temps.

    Think about it for a moment in terms of a natural setting:

    Do plants get red/blue light in the forest? Or below the water's surface buried under many other leaves that absorb those wavelengths??
    No, they get more green and less Red. So how do they still grow and photosynthesis if they cannot use those wavelengths for growth and why have those lower leaves to begin with??
    This can be intra and inter specific light competition......it can even be on the same plant or group of the same species clonally etc.
    Water depth, tannins, turbidity etc, also has an effect.

    More light increases the the rates of growth, and that means less time for development of Chl which is harder to make and not added to regions of new growth as fast as the other pigments lacking N. So it is more a developmental issue rather than the plants having more red pigment. The Chl just has had less development time rather than the higher light driving more production of red pigment per unit area of leaf.
     
  7. dutchy

    dutchy Plant Guru Team
    Lifetime Member

    Joined:
    Jul 6, 2009
    Messages:
    2,280
    Likes Received:
    4
    Local Time:
    8:44 PM
    This is misunderstood a lot. Plants that colour red is more a syndrome than a virtue of health. That's why I keep the light relatively low (80 mmol). Good growth, health, strong plants, no stunting and no problems with algae. Yes, my green plants stay green. Too bad that is mostly seen as a shortcoming.

    I've tried various bulbs between 3000 and 10000K. I can't detect any mentionable difference in growth, only in colour because of the difference in reds and blues from the bulb.
     
  8. ShadowMac

    ShadowMac Lifetime Members
    Lifetime Member

    Joined:
    Mar 25, 2010
    Messages:
    1,043
    Likes Received:
    13
    Local Time:
    8:44 PM
    See, I don't see it as a health issue particularly in the 30c. The stem growth is thicker, leaves look fuller and seem to have a good shape. I could take the plant out of one tank and compare to the less colorful one in another tank under the same type of light and see a noticeable difference in color. The increased stem size, leaf color and shape, and generally better looking plant is the same plant after a lighting switch. In this case it is not the perception..in fact the redder/pinker plants are in a tank without the pink colored bulb at the moment. (I'm thinking of dropping the flora bulb)

    I don't disagree that strong green growth under lower lighting conditions is easier to maintain.
     
  9. Tom Barr

    Tom Barr Founder
    Staff Member Administrator

    Joined:
    Jan 23, 2005
    Messages:
    18,694
    Likes Received:
    728
    Local Time:
    8:44 PM
    A 30C? A small little tank and often the bulbs for smaller tanks are poor producers watt/for Watt vs the larger, longer bulb types.
    The Watt and the spread on my 120 or 180 is very different than the spread on a 30C.

    I also can mix and combine various colors, this is an issue for smaller and nano tanks.
    The other big issue is that smaller tanks have a much larger impact with evaporation compared to a larger tank and few use sumps on such tanks, so the degassing rates change a great deal. I ran 8 nanos for about 2 years and hated it.
    If I did not top off often, that would lead to low CO2 and algae. Everytime.

    If you have a rack set up for nano's, then you can use the larger and multi bulb systems. In most cases though, you are stuck with 1 junky bulb.
     
  10. ShadowMac

    ShadowMac Lifetime Members
    Lifetime Member

    Joined:
    Mar 25, 2010
    Messages:
    1,043
    Likes Received:
    13
    Local Time:
    8:44 PM
    The 30c is running an ADA aquasky, that has been the change that improved growth. The other LED's in comparison provided decent growth, but nothing like this newer light. The plant response was immediate because the light was much more intense pearling was rapid and color improved within a few days. This tank has been the easier to get right for me. I get some algae on the glass but that is because of the window that hits it in the morning. the other panels not exposed don't get the algae.
     
  11. jcgd

    jcgd Prolific Poster

    Joined:
    Jun 8, 2012
    Messages:
    44
    Likes Received:
    0
    Local Time:
    8:44 PM
    Something changed when I swapped in 12 warm white xmls for 12 cool whites in my led fixture. I have 28 XML total, and used to run 100% cool white. The colour was very crisp before, like a very clear day with no clouds or fog. The light itself was beautiful, but the only thing that looked good under it was green. The plants looked washed out and only a few colours looked good. Purple and pink were kinda nice looking, but red was missing.

    Anyway, the look is much more yellow now, but the plants and fish look much better with the warm whites. I have Ludwigia repens 'rubin' that has shown the biggest difference. It had a smidge of colour, but since the change it has been taking on a bronzy red colour. When I first got my Hygrophila 'bold' it was a nice rich green with purplish tones to it. Very prehistoric looking. Under my light the green stayed nice, but the purple hue faded. It's coming back now. My Pogostemon stellatus was completely green before the warm whites, even the underside of the leaves. They are slowly colouring up now and are showing some pink around the nodes.

    The only thing I've changed was swapping in the warm whites. Co2, par levels were kept the same, although the warm whites may register different to the par meter. I did however find I was getting a bit of red before the LED swap (although it looked washed out) so around the time of the swap I upped my dosing to insure I wasn't accidentally limiting nitrates and forcing the reds. In my opinion this strengthens the hypothesis that the warm whites should get the credit for the better colouration, because if the nitrates were limiting before, they would be less so now. And the colouration is better/ getting better.

    The day I swapped the LEDs there was a noticeable difference in the look of the plants. They appeared to be different colours instantly, although the effect was subtle. In the week since, the colouration of a few plants has changed drastically. Mostly on new growth, but also on old growth, like the Ludwigia. I trimmed the stellata (I have to trim it every couple days) and so the new, more colourful growth is appearing further from the lights. So I can't attribute the colour change in that particular species from being closer to the light.

    My LEDs are 20" above the water and 40" off the substrate. The par drops by around half from top to bottom if you are directly under the lights. Around 140-170umol at the surface and anywhere from 20-80umol on the soil. I'm just adding this to point out that I don't have the extreme increase in par as you get nearer to the top of the tank like many people have.

    This photo is with all cool white xml (for main power, I have rb and nw xpg for colour temp adjustment which add little to no par). The photo looks as accurate to real life as I am capable of.
    [​IMG]

    This next pic was taken the day I swapped in the warm whites. It's an iphone pic and it is a horrible pic, but you can see some differences. I had also trimmed. The pic is unfortunately blurry and overexposed.
    [​IMG]
     
    #11 jcgd, Aug 23, 2012
    Last edited by a moderator: Aug 23, 2012
  12. Tom Barr

    Tom Barr Founder
    Staff Member Administrator

    Joined:
    Jan 23, 2005
    Messages:
    18,694
    Likes Received:
    728
    Local Time:
    8:44 PM
    Good reds etc with LED's is a PITA, switching them in/out requires a special build plan from the start and a lot more cost to play around.
    I can switch out the T5's all day and night for 10-15$ ea.
     
Loading...

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice