In the guide it says use cfl bulb for the first couple weeks, any cfl or a grow cfl?
I use a true 55w 5600k for first couple weeks and have great tesults
1 Like
Ok thanks , I have a qb 135 do you think I could use it from start to finish
1 Like
What size area is it covering? And is it a 3k or 3.5k light?
1 Like
3500 and a 2x2 tent I’m only doing one plant at at time
Why are you saying use a 5600k light?
A 6400k light is what works best, unless. I’m Missing something.
It is explained here in the guide https://www.how-to-marijuana.com/marijuana-grow-lights.html
@Bigguy60 that qb will do you great, it’s not going to do any harm in veg if you can keep your Temps and RH under control, I am still doing an experimental grow On 3k from seed to finish. The plants will use the light so its not being wasted but how efficient is it… Meh not very but eh if you want the best for your plant and don’t mind an extra 20$ spent on a month worth of electricity then do it.
Have the CFL nice and close, but not to close.
Remember that CFL’s have a very limited reach, about 6 inches, any further than that and light intensity is very limited.
2,000 to 2,400 lumens per sq. ft. is adequate; over 4,000 puts you into solid grow area. Over 5,000 is great. Some even suggest slightly more.
( http://www.growmedical420.com/how-many-lumens-or-watts-per-square-foot-of-light-do-i-need/ )
I woild suggest at least 16,000 lumens of cfl for your grow or 200w, at the very minium!
Most 23w CFLs put out around 1650 lumens.
Sunblaster 200w 6400k bulbs produce 14,000 lumens so they are a good start if you can get a cheap reflector/ 200w rated socket the all you would need to do is add 2 additional smaller CFL’s on each end of the reflector to boost it to an optimal veg for your chosen one.
You already have a great flowering light so I suggest you combine it with a great efficient veg light, setup.
That’s all that they had
Fair enough, but don’t forget to give advice on what to purchase for the OP.
@dbrn32 should have a look
1 Like
3500k QB 135 perfectly fine seed to harvest in a 2x2. Start it high or dimmed and watch for signs of stretching, increase intensity if you see it.
@Nicky in terms of spectral distribution. There’s very little difference between 5600k and 6400k. Even 4000k is primarily blue light.
4 Likes
Thanks Dbrn32
As I know your the guru on this, could you share with us any info? Ide love to understand it more as I’m sure some others would I may be missing a guide or a post you have already posted but if you have it handy let me know.
This chart shows most common cct options from bridgelux. Without a change in color rendering index, a 5600k would fall between 5000k and 6500k. As you can see, there’s not a big difference there, so that gap in 5600k to 6500k would be even less.
A change in color rendering index and/cct would be more dramatic difference, but that wasn’t really the difference. A 3000k cct in 80cri is quite a bit different than a 3000k in 90cri
4 Likes
Hmm interesting to see. Would be nice to have a opaque filter over it to show what cannabis prefers in flower/veg and thus could relate that information a fair bit better.
Does anyone even list the CRI? Or do you generally have to measure after purchase
They’re listed at component level. I can spec leds from around 70cri to 97cri.
Here is that other information
2 Likes
Nice.
Okay that explains the wavelengths and cannabis absorption but I’m still missing where the temperature comes in.
One can buy full spectrum lights in different temperatures soooo that’s what seem to be so confusing. I’m missing something…
When I got my light for example IW as offered it in white or burple and I choice white full spectrum obviously. This was the graph I was given
‘full spectrum’ is used very loosely,
technically your graph on the left shows every color thought to grow cannabis,
the chart on the right has the greens and yellows previous thought useless,
as far as a ‘white’ ‘full spectrum’ light goes in different colors…
the new COB and QB LED’s have all the colors available in varying amounts,
the ‘color/temperature’ denotes how much of red and blue colors are available,
a 3000k will have less blue and more red along with greens and yellows,
a 4000k has more blue and less red…
1 Like
While I understand that about the temperatures in k I just don’t see it that well I Geuss… Even though @dbrn32 posted that nice graph and you can see differences
I am basically relying on memory of 3k flower 4k above has more blue so veg and 3.5k sorta in the middle but still more blue than 3k to make a considerable difference.
I also know this from experience as I attempted a grow on 3k full spectrum COB LED’s
Lots of people growing seed to harvest with 3000k leds. Very successful grows too.
K I’m gonna tag you in my other post then… Lol
1 Like
That’s fine. Would you like me to bring some of the members there with well documented journals growing seed to harvest with 3000k?