What ratio for my red/blue supplemental light.

I'm getting ready to pull the trigger on some red/blue 3 watt leds and want to know your input on the ratio. I have read 3:1 red to blue. I intend to use it as full time supplementation. I am thinking 2 30" bars per fixture with 8-9 leds on each bar. That will depend on ratio.

I am looking at blue 445-455nm and red 610-639nm.

Using square tubing as a sink and a small fan inside one end pushing air through to actively cool.

for flowering 4:1 prob. people say above 25% blue inhibits growth

If you have white light, that is enough blue so you may want to just go all 600nm+ and toss in some far red.

Depends on the temp of the white light you are supplementing

I have 12 3500k and 4 4000k. I only wanted blue for internodal space, but I mostly play with indicas anymore so that is not a huge deal anyway.

Lots of blue. Go red.

Use blue for veg and red for bloom, and wire them that way. Use switches to turn either blue or red on. You can use red during veg, but you do not need additional blue during bloom if you are using 3500K COB's, already enough blue. Red supplement Deep Red and InfaRed (IR) are great, and Far Red for 30 minutes after lights out. peace

Ok. So upon further reading etc... I am leaning towards bars of 630 mixed with 660. I am thinking 3:1 660/630 or 2:1 660/630. And possibly a couple small far red initiators bars. The thing that interests me is the possibility of being able to go lights on more than the 12/12 which would be good for yield. Anbody have experience with that?

Well there is some research out that suggests wavelengths over 700nm has an impact on the photoperiodism functions in various plants. Suggestions for 30 min cycles straddling the on/off changes seem to be those most commonly used; definitely in the infancy stage of research.

Feel free to take up the charge yourself and contribute the results back to the community.

I would add some blue lower down as it can help stop mould issues plus the lower of most plants don`t get much blue light kinda why the tops amber up 1st

630nm leds do pretty well I`d go with them 3:1 with 660`s and lower down I`d go 7:1 red to blue sounds like you already have a good basic light set up your just adding weight right ?

That is a great idea - maybe a couple of uv chips for pest control.

PhotonFUD said:

That is a great idea - maybe a couple of uv chips for pest control.

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Yeah I was toying with firing a cool white cob just about pot level, just to lower mould risk I mean I notice the few bits of rot I found seem to be lower on the stems but where the bud starts to get heavy, only on the odd plant and only like one bud

but made me think when I was building my side light, hmm maybe 3000k`s shooting at the upper of the plants and a 5000k hitting lower down

in the end the way the light went together I ended up with a 5000k on one side of it and a lower 3000k and a higher 3000k but I just aimed the 5000k at my finishing area (mostly cool whites) and the 3000k`s at the red end and middle of the bloom area, just when your jamming cobs and heatsinks into an old hps aircooled hood, it don`t always end up set up the way you pictured it when you get done with the fans and ducting and tape.... lol

PhotonFUD said:

Well there is some research out that suggests wavelengths over 700nm has an impact on the photoperiodism functions in various plants. Suggestions for 30 min cycles straddling the on/off changes seem to be those most commonly used; definitely in the infancy stage of research.

Feel free to take up the charge yourself and contribute the results back to the community.

Click to expand...

I have been reading about the emerson effect and the gist I got is that with far red, since the plants sleep sooner that I could possibly not do a 12/12 and have lights on more than 12. It would be an interesting experiment.

THE KONASSURE said:

I would add some blue lower down as it can help stop mould issues plus the lower of most plants don`t get much blue light kinda why the tops amber up 1st

630nm leds do pretty well I`d go with them 3:1 with 660`s and lower down I`d go 7:1 red to blue sounds like you already have a good basic light set up your just adding weight right ?

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I am officially scrogging now so lower light (weight) down below isn't a big concern, although it is something I have thought about in the past. Also, they are lollipopped so any gains wouldn't be worth it So just top light for the canopy. Although the mold thing sounds like a good benefit. Although with air circulation and the lollipopping is not really an issue I deal with.

I think I am just going to go with all red for now Using cheap ebay 3 watt 20mm stars. Not top quality I know, but this is more for me to see the benefit on a budget. Costed out I am looking at abt $88 for 4 30" actively cooled fixtures with 10 leds per bar. I'm plan to use 1" square tubing instead of finned heatsink. Then if I go with far red, I will make a couple stand alone smaller 730nm initiators.

If all works well I can always upgrade to higher quality leds. $22 per light bar sounds pretty good though to start.

You could also add 8 blue and deep blue LED's on each bar and a switch to run either completely red or blue.
Using the blue one's "only" for an additional week can rise the thc levels by up to 30%.
No clue who have done this research but have seen a video on youtube and it was also mentioned here in some forums.

You can also try to use the tiny 10w china COB's instead of 3w LED's and run them on only 350mA(2-3w). They are really cheap and far more efficient as the 3w'ters when driven low. And they are available in most of all colours incl. UV, actinic blue and far red.

Just add more whites.

Randomblame said:

You could also add 8 blue and deep blue LED's on each bar and a switch to run either completely red or blue.
Using the blue one's "only" for an additional week can rise the thc levels by up to 30%.
No clue who have done this research but have seen a video on youtube and it was also mentioned here in some forums.

You can also try to use the tiny 10w china COB's instead of 3w LED's and run them on only 350mA(2-3w). They are really cheap and far more efficient as the 3w'ters when driven low. And they are available in most of all colours incl. UV, actinic blue and far red.

Click to expand...

I thought about the 10w but want to do this as cheap as possible just to see the efficacy. I have a $10K bill coming up soon on a property I own so pinching pennies wherever I can. Fucking sucks!

So I finally ordered 20-620nm, 20-660nm,20-730nm 3w leds. I plan to put 10 of the 620 and 660 combined on 30" 1 1/4" square tube with a 25x25mm 2.5cfm fan inside one end of the tube pushing air through the tube. They will be driven by a 20w 650ma driver per tube. The 730nm leds will be on seperate sinks and ran for 30mins twice a day.

I am curious to see if anyone has a similar experience in the sense of heat. My concern is that from reading about the heatsink material on steves leds that if I run more than 2 leds per 10" of tubing that heat will be too excessive and that according to the info there that any fan other than their pressurizing fan will not work. I don't want to burn my shit up, but would like to run 10leds per bar if possible for a total of 4 tubes with 620 and 660's and then a couple smaller tubes consisting of the 730's.

So basically, does anyone here have experience using square tube as a sink and if so, how many lights and what length? And what was the experience with that? Or anyone do anything similar with angle aluminum?

20w/tube - efficiency at what? Difference is the heat.

I think you would be more than ok dissipating up to 20w passively on that length of material. USB coffee cup warmers use 5w for reference.