Hey Rygh what threads can you point me to them? on this site?
Hey Rygh what threads can you point me to them? on this site?
Yes, on this site.
Board index / Algae Scrubbers / Algae Scrubbers / LED lighting.
Active, so at top.
Various posts in there reference some interesting information outside.
I got this from another site. I find it interesting and possible helpful ( like anything on the internet ? first)
"Plants only require red light for oxygen evolution (turning light into energy). Blue light is only required for responses that shape the plant's growth such as stem growth inhibition and leaf shape and orientation. Some plants have responses based on input from ranges outside red and blue (read: cucumbers).
The wavelengths most people show for chlorophyll are in vivo. The in vitro wavelengths are actually higher, around 650 nm for chl b and 670 nm for chl a. Furthermore, one study I read showed that the normal a:b ratio of 3:1 can be altered up to 6:1 with more desirable effects using that much more a-stimulating light. That being said, exclusive 660 nm light seems to me the best available solution at this time due to the unavailability of 650 nm or 670 nm LEDs.
The PAR standard calls for 25 moles/m2 per day. This converts to about 440 W/m2 (this is my own math based on this document), though I suppose the 400 W/m2 stated previously in this thread is also adequate. Optimally, you want your red light split 3:1 (300W:100W) for a standard ratio (or 6:1 - 343W:57W - for a possibly enhanced ratio) between 670 nm and 650nm, respectively.
Blue light responses are maximized with 8-20% of the red light (so 400 W/m2 red would require maximally 80 W/m2 blue). These responses have a broad range with multiple peaks between 430 nm and 480 nm which means pretty much any blue LED will do fine. (I'm aiming for 460 nm)."
Wikipedia says "Measurement of the absorption of light is complicated by the solvent used to extract it from plant material, which affects the values obtained"
Is there some etiquette for copying a post from another site? Posting links? I at least think I have not taken this to far out of context.
"Red around 650 and red around 670 are still both red and, in a living plant, are the peaks for stimulating chl a and chl b. The problem with using something lower than 650 nm (such as the 630 nm reds) is you are mostly only stimulating chl b. This causes an imbalance in the chl a:b ratio when compared to plants grown in sunlight. Also, because there is more chl b in PSII than PSI, the rate at which PSI can process electrons falls behind the rate at which PSII can supply them. What does PSII do with this energy that it can't give to PSI? It begins non-photochemical quenching in the xanthophyll cycle in which the carotenoids take the excess energy and dissipate it as heat. During this process one carotenoid (such as violaxanthin) is changed into another (such as zeaxanthin). Eventually you run out of carotenoids to convert and dissipate energy and once that mechanism is saturated the plant begins experiencing photoinhibition. The charge caused by the light exposure has no where to go so eventually causes irreparable damage to the D1 protein in PSII and the whole system stops working. Thus, you have a plant with unbalanced systems and a bunch of broken PSII floating around."
This person's comments do seem to address some of the problems I think people might be having.
Correct wavelengths(especially considering the narrow wavelengths of todays leds)
The right ratio.
By the way I got my (6) 10 watt deep reds running yesterday with the meanwell CLG-60-24 2s3p
I want to test the voltage across each branch, to make sure any one branch is not out of sync, but even with sunglasses they are to bright.
Hope this helps.
This would also explain why warm white LEDs, don't really work that well either.
Looking at that curve, they are FAR stronger on the shorter wavelengths.
- peak at 600.
- looks to be about 30% at 670.
It also means that adding warm whites to cover other wavelengths might in fact be counter productive.
Unbalances the red.
I might order some deep reds soon as well. But been busy on my sump.
For LED brightness issue:
I always do it this way:
1) Solder 4" colored red/black wires to the LED first.
2) Then mount to heat sink.
- once mounted, a pain to solder, and I have a very good soldering station.
3) Drill holes in heat sink, and run wires through hole to the back.
Then, you do all the wiring, testing and everything on the lead wires, on the back side. Never touching or near the LEDs again.
Solves the blinding light issue. Also really reduces chances of damaging the LEDs.
(Well, unless you stupidly set the led's face down on a screw lying on the workbench. GRR)
So really a 3.5) Put something on the LED side of the heatsink/etc to protect the LEDs.
BTW: Was there an ESD protection diode on the ones you bought?
- I did not see it on one I was looking at. Bothered me. Be careful of cheap star manufacturers.
For that matter, where did you buy them?
- Seems like a lot of places are out of stock.
Not sure the voltage across an LED will give you the exact answer though. Vf can vary a fair amount.
With what I think you are doing, often good to have a precise resistor in the branch, on each chain.
- gives you something to measure, and helps load-balance. But burns power.
But I never bother. I just do a single chain on a simple constant-current supply. Costs more, but lazy I guess.
Thanks for the infoOriginally Posted by rygh
Your point is well taken. I chose to match the (6)10 watt deep reds with only (6)5 watt warm whites
so as to not over do the red spectrum. Time will till if I should have tried something even smaller
( 3 watt ) The warm whites I am about to set up,waiting on nylon washers, are going to be run
with the eln-30 I could lower the current some. Will try to see what works.
(Correction) There IS esd protection. My fault they are so small I missed it at first. Mouser.
Thanks for help.
I found some, what I think is valid, info about the chlorophyll absorption spectrum.
------------------In organic solvents---in cells----------------------occurrence
Chlorophyll a-------420,460--------435(670-680)-----------all photosynthesizing plants
chlorophyll b-------453,643---------480,650---------------higher plants and green algae
chlorophyll c-------445,625-------red band at 645---------diatoms and brown algae
chlorophyll d-------450,690-------red band at 740--------reported in some red algae
There is something also mentioned about a rare chlorophyll e that is found in
golden-yellow algae. I have notice some people posting about yellow algae in
this forum whether it is same ? or why it is even important just thought I' d mention it.
Hope this helps.
Hi guys its been awhile since I was last on here, back on the mission agian Im pretty sure I can get what ever spec i need made in the quad band led just looking at some of the charts for the chlorophyll and what about lower than 400nm purple range Sm posted a graph a few pages back that had some high levels in that range.. any thoughts?
A light with a range of purple to high blue then orange to high red would this be the go?? maybe some white just in case??
Update on the 3w led globes I had, well they have been removed they may have worked if the spread was better they were just to pin pointed in the one spot at the height i could get them, having the effects of when a flood light is too close to the screen. just outside that radious was growing algea put the watt level imo was just not that great. since then I have jammed a single old t5 in there and am having beter results with algea on the screen and in the tank not really seeing a decline of algea in tank but a goni that has been difficult to open up has really started to extend alot now so im led to belive that water quality is getting better. ( sorry Im a fiend for not measuring water parameters)
looking forward to tweaking the the ats for better results..
Cheers guys for the path Im on...
I just added 4 rebel royal blues(min 440 max 460 typ 447) and 2 rebel blues(min 460 max 490 typ 470) in the first row
of a 7 "x10.5"x3" inch al heatsink.(4 would suffice)The second row consists of (6) 10 watt deep reds (660) and
the third (6) 5 watt warm both ledengin. I am getting good growth, been only 3 days since the new addition,
but I am playing around with different forms of diffission. Right now I am using
decorative/privacy glass and ?wax paper?. My second al heatsink consists of (5) rebel
cool white and a red with a 10 watt red an a 10 watt warm white from ebay also
getting good growth. I have not used another type of filter or light for several weeks that
includes sponge or overhang, which I was using for mechanical filtration i.e. replaced
filter floss often. Still thinking about going vertical because even though my discus
seem happy I am wanting to see the algae scrubbing, mass growth, that I see from more
traditional vertical scrubbers w/ more traditional lighting. Like the idea of not being
concern with the amount of food I feed the fish. A couple tips take it for what it is worth.
I used screws and nylon washers to attach my leds because it is the best way to get rid of the
heat. But the adhesive pads seem like,never used, they would be much easier to diy and the
difference in heat transfer probably does not make that much difference. My thinking
was if you setup something that lasts as long as some of these leds, just do it. Still wish I did it
with adhesive pads. This leads me to my second tip none of this is cheap after you buy all the
hardware you could save some money and aggravation by getting adhesive pads.
I am in for say $500 for the lighting. More than I want to think about. My only solace is that I
will not be needing to replace these lights for many many years.
Hope this helps.
Regarding adhesive tape:
There are really 2 issues. First is a bit lower heat transfer as mentioned.
Second is that if they get really hot, adhesive can melt and let go. Since this are mounted upside-down, they will fall off.
I would say that over 5W, you really need to look into the data sheets and details. Probably fine if less.
It worked well on the heat sinks on the rams on my graphics card, for years.
Agree that screws are a DIY pain. And if the washer cracks/melts, you can get shorts.
I really like arctic silver thermal epoxy. Great heat transfer. Very permanent.
Easy to mix, loosely clamp with clothespins/tape.
As a bonus, it is electrically resistive, so even less chance of shorts.
But you do want to wait overnight for it to harden.
And to replace it, you have to literally grind it off. (Or simply put a new one next to it)
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