Improved Color LED thread

Discussion in 'DIY' started by rygh, Oct 4, 2010.

  1. sfsuphysics

    sfsuphysics Supporting Member

    I too notice that LEDs (white ones) are REALLY good at growing algae, probably has something to do with that huge hump in the green-red area that makes the blue phosphor look white. Little "pucks" I've made are essentially 4:1 RB:CW and algae still forms, I know it probably is an underlying issue with nutrients as well, but this was with a tank with next to no feeding, and a skimmer.
  2. rygh

    rygh Supporting Member

    Well, from turf scrubber experiments, where I deliberately grow green algae:
    - Standard warm whites grow algae very well.
    - Your normal royal blue + cool white can grow algae, but not great.
    - A lot of Red + a bit of Blue + a bit of warm white seem to grow algae the best.

    A picture of the CW+RB versus Red+Blue test is here,
    where I had my CW+RB tank lights on the left, and red+blue turf lights on the right,
    although a bit hard to see because of bad lighting.

    Overall, I have really not heard much about increased algae problems when people switch to LED.
    But I certainly have heard of problems getting coralline to grow.
    For me: Green / hair / bubble algae did not increase, but I do have issue with lack of coralline.
  3. Coral reefer

    Coral reefer President

    I've heard whispers of missing spectrum in accounting for the coraline lack. What is your take on why it is lacking? What spectrum is missing/needed more?
  4. rygh

    rygh Supporting Member

    I have three wild guesses.

    Guess 1: They are missing in the Cyan / Green.
    A) LEDs are bad in that area.
    B) The color of the photosynthetic life is often the opposite of what they need.
    (What you see is what is not absorbed)
    So green algae likes red + blue, so it is green.
    Coralline varies, but it is rarely dark algae green.

    Guess 2: They are missing the deep blue / purple wavelengths, near UV.
    A) LEDs are bad in that area, even Royal Blue.
    B) That is a known requirement for terrestrial plants with more complex breeding cycles.
    A lot of garden places recommend that during flowering.
    C) Those wavelengths are stronger deeper in the water. Since the reds get wiped out pretty quick.
    So it makes sense they would be better adapted for that.

    Guess 3: Adaptability
    The wavelength issues with LEDs are an issue for photosynthetic life.
    Green algae is a much simpler beast, there is a lot of variation, and it seems to grow/die/grow faster.
    As such, perhaps it can adapt to the lighting better or quicker.

    Could be all of the above, or something completely different.
  5. bayview

    bayview Guest

    Here is my neon coral color light; Mounted on a 2x2 copper heat sink to minimize color banding and annoying shimmer;
    [img width=800 height=600][/img]

    [img width=800 height=600][/img]
  6. Piper

    Piper Guppy

    I have two 10K Kessil's and a 50/50 Reefbrite strip over my tank and the coraline algae grows OK for me. I've had that lighting over the tank from the get-go (~6 months w/ lighting) so I can't really compare it to anything else unfortunately. It did take ~3 months to really kick in and start growing what I'd consider "well". I have a couple of different colors (greenish yellow) of coraline growing too. At least I think it's coraline. I don't have enough knowledge in that area yea to be 100% sure of that statement :)

    I think it definitely has something in the Kessils. There is a definite arc on the back of the tank where the Kessils hit where it grows much better.

    I had no problems what so ever growing the brown, green and hair algae with the LEDs :/ I just got to the point about a month ago now where the hair algae has all but died off.

  7. bayview

    bayview Guest

    For the Coraline algae It could be multiple factors;

    Maybe not enough 400-430nm blue or To much green / red encouraging other algae to out compete it
    [img width=600 height=480][/img]
    [img width=800 height=600][/img]

    I noticed allot of company's say they use cree 10k cool whites; but they only make 8300k .... ?

    I used 6500k Crees at a 1/1 rb ratio; I think this is bumping up the algae; Might need to add more blue or dim the whites / have them off when not home

    8300k cree

    7000K cree

    6500k cree

    10000K bridgelux

    Here are some pics of the array on the frag / holding tank
    [img width=800 height=600][/img]
    [img width=800 height=600][/img]
    [img width=800 height=600][/img]
  8. rygh

    rygh Supporting Member

    Interesting note about the Kessil.
    (IMO : The best off the shelf LED)
    I did talk to them a bit last year at BAYMAC, and if memory serves, one thing they mentioned
    was that they added a bit on the deep violet end, beyond the normal royal blue.
    Seems that way double checking their drawing on their website.
    That would fit in with the concern about missing light in the 400nm range.
  9. Coral reefer

    Coral reefer President

    Tanks I've worked on with 50/50 reefbrites seem to grow coraline okay, not great though.
  10. yardartist

    yardartist Guest

    My coraline fades out in color to a pale pink when it is in direct line of my LED. Under ledges it keeps its deep magenta color. I have never had fast growth with it under any lighting. I feel like it is bleaching the coral as in too much intensity.
  11. CarrillXXP

    CarrillXXP Guest

    This link/thread is probably the most up to date in our hobby right now. Idk if you guys have been following along, but these guy's are coming up with builds that are creating trends in fixtures.
  12. rygh

    rygh Supporting Member

    T5 test
    Since I had a fair bit of old equipment lying around, I decided to try adding
    a single T5 bulb. The idea was to fill in the missing spectra, and perhaps make things
    look a bit better. A quick hack job.

    I specifically chose a UVL T5 V-HOR AquaSun
    It has a pretty wide spectrum, and in particular adds some violet and green.

    Not surprisingly, one 34 inch bulb did not make that much difference.

    The plus side:
    It did seem to be filling in missing spectra.
    Certainly some of the greens and yellows were filled in.
    A lot of the change interestingly was that things looked a little bit sharper.
    The improved color rendering (CRI) is likely why.

    The down side:
    It made things look rather yellow.
    Probably more realistic and sun-like, but not something I am really used to.

    So the results were mixed. Needs more thought.

    Pictures would be pointless. Camera cannot capture the difference.

    It is funny though : I used to use these bulbs on my old system, and they
    were definitely pinker there. But I used an icecap ballast then, which
    overdrives them a bit.

    I am debating trying a "Purple Plus" or "Aquapink" bulb.
  13. Piper

    Piper Guppy

    Mark - Any updates on the T5 test? I have 2 10K Kessils w/ a ReefBrite 50/50 over a 36" tank and was thinking about adding some T5 actinics to supplement and get a little more light over the tank. I've kind of been holding out for the new Kessil A350 (or what ever it is) mainly because I wanted to keep it all LED.

    I have a couple of SPS frags that seem to be doing OK but I wouldn't say they're spectacular or have great color. LPS and softies on the other hand are doing very well.

  14. rygh

    rygh Supporting Member

    I decided I will not be using T5 supplements.
    The hassle of the extra lighting is considerable. Testing was not so bad, but truly integrating
    it into the fixture is a pain.
    The benefits of just a small addition will be pretty small.
    So it is just not worth it.

    Longer term, I do plan to add some Violet LEDs, and see how that goes.
    But there are a LOT of to-do items in front of that. So may be a long time.
  15. Piper

    Piper Guppy

    That's good to know. I think I'll hold off a little longer and see what the new Kessils look like. I have most of the hardware laying around to put in T5s but I'd still need to pick up a couple of things to test it out. I'd rather put that money towards new Kessils if they look promising :)

  16. rygh

    rygh Supporting Member

    Apogee MQ-200 PAR meter results.
    Posted both here and in my LED build thread.
    Thanks BAR for getting one for the club!!
    Pure LED lighting, meter set to "sun" mode.

    For normal mid-day setting:
    (Left / Right)
    2 inches = 100-250 / 100-220
    6 inches = 150-180 / 130 - 150
    12 inches = 130-150 / 80-120
    24 inces = 60-90 / 50-70

    It is interesting that left is that much brighter. The difference is that the LEDs on
    the left side each have a short 1" PVC around them, as a "reflector lens" of sorts.
    I think I might tweak the right side up a bit.

    Most of my hard corals are at the 12 inch depth.

    The very front is quite a bit lower PAR. Around 80-90 at 12 inches.

    I also measured the LED fixture on "full power".
    I had to turn it down several times due to bleaching, so normal is a lot less.
    I only measured left side.

    2 inches = 270-350
    6 inches = 180-220
    12 inches = 180-220
    24 inches = 100-140

    So the fixture is capable of about 30% more than it is running.
    That is expected, due to settings.

    Note that the orientation of the sensor is pretty critical to measurement.
    It can be hard to get consistent readings.

    Just FYI, from updated code: Value = N/255, so 255=100% on.
    // left
    pwm_level_l_red = 136;
    pwm_level_l_rblue = 200;
    pwm_level_l_cwht = 180;
    pwm_level_l_nw = 255;

    // right
    pwm_level_r_red = 136;
    pwm_level_r_rblue = 230;
    pwm_level_r_cwht = 190;
    pwm_level_r_nw = 255;
  17. rygh

    rygh Supporting Member

    Side note:
    One thing I was really happy with was the uniformity at 12 inch coral depth.
    Other than the very front, very back, and ends, it was quite stable.
    No lenses!
    The range on the measurements was really more accuracy issues than variations
    over area.
  18. rygh

    rygh Supporting Member

    Interesting data point on Coraline issue:
    I ended up using leftover parts from my main display tank lights to make a fuge light.
    The fuge light used two clusters nearly identical to the above thread.
    (It is not a fuge meant to grow macros.)
    One was CW/RB/CW/RB, the other was RB/NW/RB. Nice 14K-ish look I would say.

    At any rate : I am starting to get GREAT coralline growth in the fuge.
    Nice deep purple.

    The main difference : Intensity!
    The fuge lights are FAR weaker. Only two small clusters for a wide area, and quite a bit higher placement.
    Otherwise, everything is mostly the same. Light wavelengths should be nearly identical.
    In particular : the water chemistry is obviously identical.
  19. sfsuphysics

    sfsuphysics Supporting Member

    Hmm interesting, I wonder if that's why I always got such massive coraline growth on the side panels yet not as much on my rock structure. I've always used good reflectors which moved most of the light downward , some of the spill over on the sides might cause my endless headache of having to clean the acrylic of coraline.

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