Lighting LED and CalMag discussion.

[X]

Me:8/25/13

I was reluctant to do this since I try not to stray from feeding my mix/TLO. But, in my very limited experience, it has been a very obvious result of using high-red LED's. I guess I'll try it this grow unless I come up with another option. I don't want to try and add more lime to my mix... that can lead to a whole 'nuther bunch of issues, and I would have no idea how much extra cal/mag amendments I'd add to get it right.

ME:9/16/13

That is an interesting observation. Has anyone tried dropping the hours back? Could it be possible that due to the intensity and focus of LED color spectrums, 20 hrs is too much? I'm not in a position to check that out right now, but it might be something to look into...

Me:9/17/13

I only use my LEDs after the stretch and I'm just starting a new grow... (none have sexed yet). When I get to the change-out point, I'll try it. From my experience, the deficiency shows within a couple days of exposure to the LED's, so I should get some idea pretty quick.

Great thread! subbed...

Bushdktr:10/3/13

Hi there everyone! I was thinking...maybe people in the organic threads using LEDs have something to say. Most of the people that use compost (I have one at home) have plenty of egg shells in it and shouldn't have any problems when using LEDs + organic soil & nutes.

My response:10/3/13

I use TLO, exclusively... the normal amounts of organic calcium amendments (egg shells, oyster shells, dolomite, etc.) will not address this issue with the lights I use 20/4... I have about 140w (3wx80) per plant and my spectrum is swung disproportionately to the red side (bloom).

Perhaps, if someone was using less power and a more balanced spectrum, your statement may come closer to being accurate.

ME: 10/25/13

Hey guys... I just put my gals under the LED's at 50 days old. Previously, I had them under 20/4, and the deficiency started showing almost overnight. This time, I switched to 14/10 and there has been nothing so far, but it has only been three days. I have grown autos under 12/12 before, with HID's, and there really wasn't much discernible difference in the yield, but I know it probably does make at least some difference.

I'm going to increase to 16/8 and see how it goes. I'll keep you posted.

Okay... latest update with my LEDs.

The first time I used the LEDs, I also used guano teas for the first time and got the yellowing. Everyone was calling this an LED induced deficiency, and since I had just started with my LEDs, I assumed the same.

I use TLO and, until that grow, had only used water... no cal/mag, teas, nothing, except some myco's. I am now about a month into my third grow with the LEDs, and this time I went back to water only. I have absolutely no sign of anything amiss yet, in fact the plant is thriving.

So, in my case at least, it was not a deficiency... it was the result of using teas that were either too hot, or simply unnecessary.

I don't know that this would help anybody but I thought it was worth sharing. BTW, the plants are under 20/4.

Latest update:2/27/14

I pasted the quotes above to illustrate that I have been following this thread from the beginning, that I have been all over the place trying to figure it out, and because I feel I owe Bushdktr an apology. It would appear, He was right. I was wrong. After two complete, start to finish, grows with no issues, I am confident it is a nutrition issue for the most part.

I use TLO, exclusively. You can't buy this in a bag. It is a very robust and well cooked mix that is a "water only" mix. I know some of you will not be able to see the image I am loading but, if you can see the pic, you will notice there is absolutely no sign of die-off/deficiency. This plant is 70 days old and has been under my LED's exclusively since sprouting. I have fed it water only... no teas, just some extra myco's pre-sex.

My plants are generally not very exceptional but they are usually very healthy, as is the case with this one. I don't have science, but my experience leads me to be convinced the issue can be eliminated with proper nutrition, without regard to other possible factors. I wish I had an answer for you hydro/coco/bagged mix folks but a good TLO mix seems to make it a non-issue.

P.S. I also have 5 photo's that are the same age but will be another month or so finishing out. Same deal... all dark green without blemish.

 

[Evo]

I am growing 4 photo plants( 3 Sweet Seeds Black Jack and 1 Sensi Seed NLxhazw) under MS006. I am in 5th week of flowering. The 3 black jacks are showing cal-mag defeciency. The NLxhaze is fine. I think some strains are more prone to this problem than others.

 

[InHumboldt]

- - - Updated - - -

I have been running LED for a few years now. I do three things different.
I use 6500k and or 2700k suplimental light. I call it fequency doping.
I am inorganic.
I see what you see-you say magnesium deficency, I say toxic overdose-lower the overfeed blocking the magnesium or overwelming the demand for magnisium.
Note how the plant put out in the sun recovers when the missing fequency of light is pumped in. So low frequency feed results in the need to patch with more of a mineral feed.
What I wonder is---- that it's not what the LED's are doing but what they are not!
Then again I've been quality assuring----my thinking may not be all it should be untill I can find were I left the Twinkies and Viseen dam it-they were sitting here a second ago-dam it!!!!

 

[Dr Cannabis]

Here's a cal-mag LED problem for ya..

View attachment 334465

I've put some dolomite lime balls in the top of the soil, buried some finger deep in the soil as well, and then watered a bit. My plants are quite skinny, but for other reasons than cal-mag def. and LED. They had almost no light for the first 22 days.

There are many variables in the equation huh.. Heat, rH, nutes, light strenght and spectrums, autos or not. Maybe we should be more concerned with what to do in order to achieve this problem, rather than what not to do. In order to narrow down the route. Who's up for wasting some seeds and watts?

My cal-mag probs arose once I switched the whole light scheme upside-down, went from 18/6 to 20/4 once they began to blossom. An experiment. The one closest to the LED light is the one you see above. Out of three ladies. The other ones look more like this..

View attachment 334466

But they have cal-mag probs too. The closer they are to the light, the greater the cal-mag problem, is where I'm at. That's a bit of info for the puzzle.

 

[TaNg]

I'm seeing a lot less calmag def now I'm using the GN Rebel upgrades and I think it's to do with the reflectors and the way they spread the light evenly.

 

[Gloomshade]

I am wondering...with so many people growing in so many places across the world... how much people know about the water they have coming out of the tap... I was just trying for like 20mins to find an extract from a water quality report i swear i read sometime in the last fortnight that actually had a calcium and magnesium content of my tap water. I gave up... and i have read waaay too many lines of governmental crap for one day... Pretty sure there is bulk calcium in my tap water though...not sure about magnesium.

 

[epenguin]

I just been looking through this thread and as an LED user it was on my list to perhaps help out with cal/mag. But as a tightwad penguin I was hoping to just get some epson salts to do the job. Would this suffice ? Where can I get it? Any feeding directions would be helpful. cheers eP.

 

[epenguin]

I just been looking through this thread and as an LED user it was on my list to perhaps help out with cal/mag. But as a tightwad penguin I was hoping to just get some epson salts to do the job. Would this suffice ? Where can I get it? Any feeding directions would be helpful. cheers eP.

 

[Arpo]

Firstly I must say that this is a cracking thread and answers some questions/problems I've been having and now throwing up more questions. I have a vast and fast at 24 days and a wipeout express at 17 days and both have small 'burn' marks on the lower/first leaves but I have seemed to have stopped this by dropping the ppm's but I think that this will be a short term fix after reading all this. Going to add some molasses and raise the ppm a little today as I won't make it to the shops for a while for some cal/mag, I'll see if that helps.

Secondly a question was asked 'Is there any feed just for auto flowers'. Answer, yes. I'm using Dutchpro A and B autoflower feed, one set for veg and another set for flower. They cost me £10 per set. If you want to see they can be found at www.dutchpro.nl I hope this helps a little bit.

 

[tokaite]

High!

Any updates on that def? Still cannot control it effectively....

Peace!