Using other led's with cob

is there any need to use he smaller led's uv red blue or do cobs have every thing all in one package?

If you add smaller LEDs you can enchance spectrum.
I am looking for that too...

As I can understand (from spectrum graph) you can add some 660, 730, and anything between 400-500 to get close to McCree curve. Also some UV.

Starts to get completed quick

I think cobs do a great job all by themselves.. not that complicated..

Ok cool I wonder if more will chime in and give there experances as well

Took a good cri90 COB and you don't need additional mono's. Look @The Dawg 's CRI80/90 comparision thread and be amazed..

https://www.rollitup.org/t/dhp-presents-citizen-cob-1812-3500k-80cri-vs-1812-3500k-90-cri.932990/

Thanks for the info

Look at all the cob grows on here and you will see some amazing quality buds. There are arguments for supplementing but the real truth is we really don't know exactly what spectrum enhancements our girls like best or how each might effect speed of growth or yield ect.
Nothing to stop you playing with spectrum later when you have a few grows under cobs to compare to.

Yeah, if you really want to add something good add a good reptile T5HO bulb as "terpene enhancher" and run it for 1-3h when the plants starts forming their first trichomes. Should increase terpenes by a few percent..

coreywebster said:

Look at all the cob grows on here and you will see some amazing quality buds. There are arguments for supplementing but the real truth is we really don't know exactly what spectrum enhancements our girls like best or how each might effect speed of growth or yield ect.
Nothing to stop you playing with spectrum later when you have a few grows under cobs to compare to.

Click to expand...

Yepp,
emerson's effect seems to be a worthwhile thing, but it is still unclear how much 660 and 730nm is needed. Somewhere between 1: 8 to 1:12, depending on COB's/CRI used ...
But still missing safe # for mj ...

I have also seen a video of a well-known, commercial US breeder on youtube who used an additional week of blue/380-450nm to raise THC levels. Reportedly it reached 31%
and 20-30% increase strain dependent...
Unfortunately, durable numbers are missing...
so remains much of speculation and even more myths..

KonopCh said:

If you add smaller LEDs you can enchance spectrum.
I am looking for that too...

As I can understand (from spectrum graph) you can add some 660, 730, and anything between 400-500 to get close to McCree curve. Also some UV.

Click to expand...

Start simple, because after you build one, you will have better ideas for the next. Just start a run or 2 with just COBs, then later add some color. I personally think a good 3500k or higher k (preferably 90cri) is the way to go and not just for flowering. I like the way the warmer K veg plants better than a cooler K. New plants don't seem to adapt to the light as fast in my garden. Even the 3500k 80cri has so much more blue than an HPS that it looks more like a MH. Even my 3000K 90cri has more than enough blue. Right tray 2 DE HPS and left tray 1950w of COBs going from (front) 4000k 70cri, (middle) 3500K 80cri, (back) 3000K 90 cri.

3000k work as good as 3500k?

Manfromthenorth said:

3000k work as good as 3500k?

Click to expand...

Yepp, better flowering and still enough blue for vegging in 3k/CRI80. But CRI90 seems to be even better on latest gen. COB's because their efficiency increased and their spectrums fits the mccree curve better as CRi80.
In fact, all CRI90 COB's will do well, whether 3,000, 3,500 or 4,000°k.
For some stretchy strains even 5,000°k can be appropriate.
Search the LED forum for some CRI80 vs. CRI90 threads.