Led's light bleaching?

on a legal medical grow the panels, (one veg, one bloom 240w blackstars) are roughly 16-18" above several plants, two in coco, two in fox farms, and two dwc..

all of the plants are stunted, all of the plants have dead foliage.

Ph is good, temp is good, ppm is good.. several of the plants have white patches on their leaves, like all the color has left. most of the plants cotledons have dried up like a nitrogen defficiency... they have been treated with micronute foliar sprays.. canazyme, rhyzotonic..

does this sound like light is to blame? it doesn't seem like it should do this, but it's the only answer i can think of.. does anyone have some good photos of light bleached leaves?

Attachment 282963

LED burnt!
First the leaf gets thick as the thylakoid disks line up edge-on and the vertical growth stalls.
Attachment 282964

Then they bleach.
That what ya wanted?

Aloha,
Weezard

welll.. sort of, here's a pic of one of the coco girls.. being fed with gh nutes, cannazyme, and rhizotonic.. foliar fed occasionally with fulvex..the water is very hard, so I'm not worried about calcium.. 1/4teaspoon of epsom salts too.. since she is fed enough, I would think it were some sort of lockout.. but, the ph is pretty damned good too. between 5.6 and 6 at all times.

ppm right around 900-1100..

looks like a nitrogen deff.. but it can't be with the amount it's being fed..Attachment 282965

Douglas1, I think you're on to something here. I have a 180W Blackstar veg and a 240W Blackstar bloom. The 180W veg light is an animal, and grows plants like nobody's business. I've now placed 3 plants under the 240W bloom light--going in, all of them were super healthy and rapidly growing--and almost instantly their growth rate dropped way, way off. Within a day or so, all 3 started showing these symptoms:

Attachment 283155.

This appears to be a sulfur deficiency. Although sulfur deficiency made no sense to me--I changed nothing except lights--I went ahead and applied garden sulfur and Epsom salt, but to no avail. The symptoms persisted.

I too have been fruitlessly looking around for light bleaching pics. Even though the symptoms of your plant look different than mine, in view of your experiences with your 240W Blackstars, the only thing that makes sense to me is light bleaching/photo toxicity. My 3 plants were placed 16" under the 240W Blackstar. One was in a 5-gal DWC tank, the other two were in 100% perlite hempy buckets. Not knowing what I was facing, I kept the DWC plant under the 240W Blackstar for nearly 3 weeks, and in that time it flat-out died. The second plant (the one shown in the picture above) was under the 240W light for 72 hours before I moved it back under the 180W veg light. The appearance of sulfur deficiency persisted, however, the plant has now slowly resumed growth. The third plant was under the 240W light for 24 hours before it too began showing the same symptoms. I've now moved it 30" under the light, and we'll see how that goes. I'm keeping my fingers crossed because 30" is all the headroom I've got, and I'm down to my last healthy plant.

My 3 experiences combined with your experiences have proven to me that 16" under the 240W Blackstar bloom light is just way too intense. This is surprising because, compared to the 180W veg light, it doesn't look all that strong. When I was trying to decide between it and the 180W Blackstar, I went to the Lighthouse Hydro web site for help. Both lights have 2'x3' coverage, and all the web site says is the 240W light is for those seeking a more intense light. Being a tyro, I figured who doesn't want a more intense light? If I had to do it over again, though, I'd go with the 180W bloom light. Mine is just a tiny, hobbyist, experimental, one-bloom-plant-at-a-time type operation, and the 180W bloomer probably would have suited me perfectly.

Quote:

---

Originally Posted by Douglas1

welll.. sort of, here's a pic of one of the coco girls.. being fed with gh nutes, cannazyme, and rhizotonic.. foliar fed occasionally with fulvex..the water is very hard, so I'm not worried about calcium.. 1/4teaspoon of epsom salts too.. since she is fed enough, I would think it were some sort of lockout.. but, the ph is pretty damned good too. between 5.6 and 6 at all times.

ppm right around 900-1100..

looks like a nitrogen deff.. but it can't be with the amount it's being fed..Attachment 282965

---

That's gotta be the worst case of nute-burn that I've seen, yet.
Never feed a too young 'ling.

Sorry, I calls 'em da way I sees 'em.

Aloha,
Wee 'zard

Quote:

---

Originally Posted by Hataman

Douglas1, I think you're on to something here. I have a 180W Blackstar veg and a 240W Blackstar bloom. The 180W veg light is an animal, and grows plants like nobody's business. I've now placed 3 plants under the 240W bloom light--going in, all of them were super healthy and rapidly growing--and almost instantly their growth rate dropped way, way off. Within a day or so, all 3 started showing these symptoms:

Attachment 283155.

This appears to be a sulfur deficiency. Although sulfur deficiency made no sense to me--I changed nothing except lights--I went ahead and applied garden sulfur and Epsom salt, but to no avail. The symptoms persisted.

I too have been fruitlessly looking around for light bleaching pics. Even though the symptoms of your plant look different than mine, in view of your experiences with your 240W Blackstars, the only thing that makes sense to me is light bleaching/photo toxicity. My 3 plants were placed 16" under the 240W Blackstar. One was in a 5-gal DWC tank, the other two were in 100% perlite hempy buckets. Not knowing what I was facing, I kept the DWC plant under the 240W Blackstar for nearly 3 weeks, and in that time it flat-out died. The second plant (the one shown in the picture above) was under the 240W light for 72 hours before I moved it back under the 180W veg light. The appearance of sulfur deficiency persisted, however, the plant has now slowly resumed growth. The third plant was under the 240W light for 24 hours before it too began showing the same symptoms. I've now moved it 30" under the light, and we'll see how that goes. I'm keeping my fingers crossed because 30" is all the headroom I've got, and I'm down to my last healthy plant.

My 3 experiences combined with your experiences have proven to me that 16" under the 240W Blackstar bloom light is just way too intense. This is surprising because, compared to the 180W veg light, it doesn't look all that strong. When I was trying to decide between it and the 180W Blackstar, I went to the Lighthouse Hydro web site for help. Both lights have 2'x3' coverage, and all the web site says is the 240W light is for those seeking a more intense light. Being a tyro, I figured who doesn't want a more intense light? If I had to do it over again, though, I'd go with the 180W bloom light. Mine is just a tiny, hobbyist, experimental, one-bloom-plant-at-a-time type operation, and the 180W bloomer probably would have suited me perfectly.

---

It is the light! my plant showed very similar symptoms to yours, but got much worse as time progressed because, not only did I think it was nute burn from too rich soil or something, and so did not fix the light issue until the girls were pretty much torched.. but my plants were also very small when I introduced them to two 240's flowering angled in on either side, and the 240veg over head.. needless to say, 350watts or so of true led consumption.. was a little overkill for the youngsters.

what has helped me now, was switching them all over to coco/pearlite mix, so I can get them nutrients quickly, and I know for certain that its not the soil burning them. and mixing up a foliar feed with micronutes, rhizotonic for the roots, and nitrogen.. I also turned off the two flower panels and put the veg about a foot and a half up from the plants. while the ones in pots are recovering slowly, the two in hydro are going full bore..

It's good to know someone else has had this problem, though its a good problem to have really :)


weezard, like I said, they had not been fed at all. I considered the soil being too rich, but the coco plants and the hydro girls all showed the same symptoms until I changed the lights. now the hydro plants have shot out new leaves, and the coco ones are slowly recovering. I planted a new seed though a week or so ago, and it's already outgrown the potted ones.. so something has changed for the better I think.

also.. how do you like growing in straight pearlite? my coco pearlite mix is roughly half and half and I love it.. seed I started straight in the mix and fed 250ppm until it had some true leaves, than 500ppm currently.. and crap, it's the fastest I've ever seen for this stage of development.. dwc you have a waiting period until it puts down roots.. this just takes off from the start.

I don't like how much gnats like it though.. you have that problem with pearlite?

Great post rocks.......
prime example why light equals mass....!

bleaching with led spectrums only prove my point....thx

I have ran all hps (finishing year now.) great calyx to leaf ratio
all mh (previous years) larger less problematic plants
all led (year before) no mass
all three..... next year expecting phenomenal results........!

thoroughly studied till my brain hurts for all you guys..... lol

Quote:

---

Originally Posted by Native¥organicfarmer

Great post rocks.......
prime example why light equals mass....!

bleaching with led spectrums only prove my point....thx

I have ran all hps (finishing year now.) great calyx to leaf ratio
all mh (previous years) larger less problematic plants
all led (year before) no mass
all three..... next year expecting phenomenal results........!

thoroughly studied till my brain hurts for all you guys..... lol

---

I don't see how this thread implies that led's don't put out mass.. if anything it proves that a light that uses about 130watts in the diodes.. is capable of giving a plant way too much light from a distance comparable to a 400watt mh. That means that my light is more efficient so far. metal halide lights penetrate better for certain, but with lst, and canopy management.. I would say we could achieve very comparable results watt for watt.

Personal Opinion,
its not the thread its the law.......
yea at the frequency of led alone does not promote mass,
but in your case bleaching and a abundance of unused output with 130 watt diodes.
unfortunately led is not comparable to mh or hps for mass.
yes more beneficial at certain frequency and placement in garden as supplemental lighting.
light mass created by either of us only penetrates 3 foot max.
with canopy management yes great results can be achieved but,
the rules of biology dont change.

So in short the only way to achieve true mass is to create it..........
and with the sun 5,000 lumens per sq inch how do you plan on achieving this with led...... Im ready to learn,
i wont argue just run all of them, great results.......

Quote:

---

Originally Posted by Douglas1

It is the light! my plant showed very similar symptoms to yours, but got much worse as time progressed because, not only did I think it was nute burn from too rich soil or something, and so did not fix the light issue until the girls were pretty much torched.. but my plants were also very small when I introduced them to two 240's flowering angled in on either side, and the 240veg over head.. needless to say, 350watts or so of true led consumption.. was a little overkill for the youngsters.

what has helped me now, was switching them all over to coco/pearlite mix, so I can get them nutrients quickly, and I know for certain that its not the soil burning them. and mixing up a foliar feed with micronutes, rhizotonic for the roots, and nitrogen.. I also turned off the two flower panels and put the veg about a foot and a half up from the plants. while the ones in pots are recovering slowly, the two in hydro are going full bore..

It's good to know someone else has had this problem, though its a good problem to have really :)


weezard, like I said, they had not been fed at all. I considered the soil being too rich, but the coco plants and the hydro girls all showed the same symptoms until I changed the lights. now the hydro plants have shot out new leaves, and the coco ones are slowly recovering. I planted a new seed though a week or so ago, and it's already outgrown the potted ones.. so something has changed for the better I think.

---

Thanks for the feedback, Douglas1, very helpful and encouraging. The more I think about your comment that this is a good problem, the more I begin to see the light. All it takes, I think, is a simple strategy change. Rather than start the plant up high and lower it as the colas develop, I'm going to start the plant down low and let the colas stretch up into the light. This is testament, tutorial, and cautionary warning to others about the penetrating power of the 240W Blackstar vegger. I've carefully read everything I could find about this light (including a grow journal where a guy pitted a 240W Blackstar vegger against a 500W LED competitor) and by all accounts this light is universally underestimated. It just does not look all that powerful, and the intuitive reaction upon first seeing it in operation is to place it about 18" above the canopy. Judging from its effects on our plants, however, this is much too close (and inefficient and dangerous) for such a deceptively powerful light. I should back up and state that my DWC plant (RIP) was trained into a magnificent 2'x3' SCROG, and my hempy plants were flattened with LST into ~2 sq. ft. SCROG-like bushes. This shaping could definitely affect distances, but my ultimate point is the 240W Blackstar vegger is not a simple light. It has a learning curve, and I suspect when we as a user community finally crack its code, it will prove capable of some amazing production rates. Anyway, at this point, just an educated guess...

Ill try to explain why its more than you think and not that simple.
However, plants are frequently seen with foliage of a variety of other colours from shades of red, brown, purple through to black. These colours are caused by other pigments such as betacyanins and anthocyanins produced in response to environmental stress, as a mechanism for filtering intense sunlight or your (led) or as the endpoint of selective breeding of desirable cultivars. These pigments are incidental to photosynthesis, but may well only be produced in plants grown in the strongest light especially with a high blue and ultraviolet content. MASS..... I'll ask you a Q?
I have all these colors in my plant leaves do have deficiency or am i intentional promoting stress training to a xx female f2 with light and environmental training being the key tools to achieve this with no chemicals......?

Quote:

---

Originally Posted by Native¥organicfarmer

Personal Opinion,
its not the thread its the law.......
yea at the frequency of led alone does not promote mass,
but in your case bleaching and a abundance of unused output with 130 watt diodes.
unfortunately led is not comparable to mh or hps for mass.
yes more beneficial at certain frequency and placement in garden as supplemental lighting.
light mass created by either of us only penetrates 3 foot max.
with canopy management yes great results can be achieved but,
the rules of biology dont change.

So in short the only way to achieve true mass is to create it..........
and with the sun 5,000 lumens per sq inch how do you plan on achieving this with led...... Im ready to learn,
i wont argue just run all of them, great results.......

---

I don't understand your argument.. are you saying that because mh lights put out more light energy they will always grow plants bigger and faster? the whole idea led's is targeting specific spectrums, so that huge amounts of energy is not wasted on useless wavelengths. I started with one light, and I liked it so much I bought two more, they run cooler, quieter, and on less electricity than metal halide lamps. they bleached my plants because I had way too much on way too little green.

I think you are saying that different colored leaves require different wavelengths in your second post? Maybe it's too late and I'm not thinking clearly but that was what I got.

the 240watt veg model is mostly white diodes, with some blue and red and uv.. so, it's not missing any magical wavelengths. I asked the company why this was, and they said that the white diodes more efficiently provide blue spectrum or something to that effect.

the blues are what you need for mass in vegging, reds for mass in flower. I have two flower panels for that. for 300 watts of led, I'm getting results similar to a 600w mh. and its fact, I've seen it myself.

Quote:

---

Originally Posted by Hataman

Thanks for the feedback, Douglas1, very helpful and encouraging. The more I think about your comment that this is a good problem, the more I begin to see the light. All it takes, I think, is a simple strategy change. Rather than start the plant up high and lower it as the colas develop, I'm going to start the plant down low and let the colas stretch up into the light. This is testament, tutorial, and cautionary warning to others about the penetrating power of the 240W Blackstar vegger. I've carefully read everything I could find about this light (including a grow journal where a guy pitted a 240W Blackstar vegger against a 500W LED competitor) and by all accounts this light is universally underestimated. It just does not look all that powerful, and the intuitive reaction upon first seeing it in operation is to place it about 18" above the canopy. Judging from its effects on our plants, however, this is much too close (and inefficient and dangerous) for such a deceptively powerful light. I should back up and state that my DWC plant (RIP) was trained into a magnificent 2'x3' SCROG, and my hempy plants were flattened with LST into ~2 sq. ft. SCROG-like bushes. This shaping could definitely affect distances, but my ultimate point is the 240W Blackstar vegger is not a simple light. It has a learning curve, and I suspect when we as a user community finally crack its code, it will prove capable of some amazing production rates. Anyway, at this point, just an educated guess...

---

I'm happy with it, learning curve for certain though.. it seems like the hydro girls handle the high amount of light better than the potted plants.. not sure why that is.

something else that's cool about these lights.. I can run two at once, and not worry about venting at all, no fans no in/out. just co2 piped in at the right ppm. no heat problems, and opening the door occasionally to check em lets out the humidity.

Disadvantages,

High initial price: LEDs are currently more expensive, price per lumen, on an initial capital cost basis, than most conventional lighting technologies. As of 2010, the cost per thousand lumens (kilolumen) was about $18. The price is expected to reach $2/kilolumen by 2015. The additional expense partially stems from the relatively low lumen output and the drive circuitry and power supplies needed.
Temperature dependence: LED performance largely depends on the ambient temperature of the operating environment. Over-driving an LED in high ambient temperatures may result in overheating the LED package, eventually leading to device failure. An adequate heat sink is needed to maintain long life. This is especially important in automotive, medical, and military uses where devices must operate over a wide range of temperatures, and need low failure rates.
Voltage sensitivity: LEDs must be supplied with the voltage above the threshold and a current below the rating. This can involve series resistors or current-regulated power supplies.
Light quality: Most cool-white LEDs have spectra that differ significantly from a black body radiator like the sun or an incandescent light. The spike at 460 nm and dip at 500 nm can cause the color of objects to be perceived differently under cool-white LED illumination than sunlight or incandescent sources, due to metamerism,red surfaces being rendered particularly badly by typical phosphor-based cool-white LEDs. However, the color rendering properties of common fluorescent lamps are often inferior to what is now available in state-of-art white LEDs.
Area light source: Single LEDs do not approximate a point source of light giving a spherical light distribution, but rather a lambertian distribution. So LEDs are difficult to apply to uses needing a spherical light field. LEDs cannot provide divergence below a few degrees. In contrast, lasers can emit beams with divergences of 0.2 degrees or less.
Electrical Polarity: Unlike incandescent light bulbs, which illuminate regardless of the electrical polarity, LEDs will only light with correct electrical polarity.
Blue hazard: There is a concern that blue LEDs and cool-white LEDs are now capable of exceeding safe limits of the so-called blue-light hazard as defined in eye safety specifications such as ANSI/IESNA RP-27.1â??05: Recommended Practice for Photobiological Safety for Lamp and Lamp Systems.
Blue pollution: Because cool-white LEDs (i.e., LEDs with high color temperature) emit proportionally more blue light than conventional outdoor light sources such as high-pressure sodium vapor lamps, the strong wavelength dependence of Rayleigh scattering means that cool-white LEDs can cause more light pollution than other light sources. The International Dark-Sky Association discourages using white light sources with correlated color temperature above 3,000 K.
Droop: The efficiency of LEDs tends to decrease as one increases current.

eventually someone will understand what im saying..............

Quote:

---

Originally Posted by Douglas1

also.. how do you like growing in straight pearlite? my coco pearlite mix is roughly half and half and I love it.. seed I started straight in the mix and fed 250ppm until it had some true leaves, than 500ppm currently.. and crap, it's the fastest I've ever seen for this stage of development.. dwc you have a waiting period until it puts down roots.. this just takes off from the start.

I don't like how much gnats like it though.. you have that problem with pearlite?

---

I love growing in straight perlite, and I totally agree with you about DWC. My DWC plant was clone from popcorn-bud cutting taken last October, and it took damn near forever to get through the bubble cloner into the final 5-gal DWC tank. My success rate was one in twelve cuttings. Most of the cuttings were lost transplanting into various media including perlite.

Nowadays I clone with Rapid Rooters. As soon as the clones pop roots, the RRs go straight into 100% perlite and the clones get a thorough watering with full strength nutes (SensiGrow AB). Growth rates with this approach are incredibly fast. These two photos are of the same clone taken just shy of 5 days apart.

Attachment 283166Attachment 283167

Veg growth was equally impressive. Incidentally, the 2nd picture was taken while euthanizing the clone, which was a backup. The success rate cloning with RRs is a solid 100% so this backup clone was not needed. The growth rate of the kept clone was even more impressive.

One thing about straight perlite, nutrient uptake is so blazingly fast that daily feedings of full-strength nutes are required. If even a single day is missed, deficiencies start kicking-in immediately. The reward, of course, is blazingly fast growth rates. It still amazes me how heavily and how fast the plants feed in straight perlite. I've never had to flush with water. Doing so would probably severely starve the plant.

One big goal in using straight perlite is to keep organic material in the media as low as possible specifically to prevent infestations, so I've avoided adding coco or any other organic media (the RRs are the one exception). Thus, knock on wood, I've never had any problems with fungus gnats. Occasionally, I'll add about 1 oz. of h2o2 (hydrogen peroxide) per gallon of nutes to knock-down algae, pests, and other accumulated organics in the perlite. If you're using organic nutes, I'm not sure if using h2o2 is good advice because it oxidizes many organic compounds.

I have yet to grow from seeds, but my hunch is the same RR->100% perlite + full strength nute approach will work equally well for seedlings. One thing's for sure, I'm not letting any future seedling of mine anywhere near the 240W Blackstar vegger.

Bottom line, I've tried DWC, aeroponics, and several vermiculite/perlite hempy bucket mixtures, and overall, the 100% perlite hempy bucket has owned all of them.

Quote:

---

Originally Posted by Hataman

Thanks for the feedback, Douglas1, very helpful and encouraging. The more I think about your comment that this is a good problem, the more I begin to see the light. All it takes, I think, is a simple strategy change. Rather than start the plant up high and lower it as the colas develop, I'm going to start the plant down low and let the colas stretch up into the light. This is testament, tutorial, and cautionary warning to others about the penetrating power of the 240W Blackstar vegger. I've carefully read everything I could find about this light (including a grow journal where a guy pitted a 240W Blackstar vegger against a 500W LED competitor) and by all accounts this light is universally underestimated. It just does not look all that powerful, and the intuitive reaction upon first seeing it in operation is to place it about 18" above the canopy. Judging from its effects on our plants, however, this is much too close (and inefficient and dangerous) for such a deceptively powerful light. I should back up and state that my DWC plant (RIP) was trained into a magnificent 2'x3' SCROG, and my hempy plants were flattened with LST into ~2 sq. ft. SCROG-like bushes. This shaping could definitely affect distances, but my ultimate point is the 240W Blackstar vegger is not a simple light. It has a learning curve, and I suspect when we as a user community finally crack its code, it will prove capable of some amazing production rates. Anyway, at this point, just an educated guess...

---

Ayah, late night senioritis, I meant 240W Blackstar bloomer, not vegger.

I’ve had the same thing happen, except my flower lights are Blackstar 180w... I’m new, so I thought I’d probably made mistakes, but it seemed odd that things went wrong within days of changing lights.

The same thing has happened on my new grow. However, I have some plants grown from seed and some from clones under the same lights. The clones are yellowing, but the seed plants are fine! In fact, I have one seed plant and one clone in the same pot, showing different results. I wonder if clones are less hardy. I've tried all the iron /magnesium /sulphur deficiency stuff.

Please keep posting your findings, I would really like to get this sorted.

So does it seem like light bleaching? Im having the same issue with the blackstars and its driving me nuts

yes! light bleaching it was, are you using veg or flower panels? I have my 240w flower panel about a foot above the plants now, and they are all doing much better. I think running the veg panel from 2ft or more would be good for this stage, then gradually lowering it as the plants mature

Good to hear....I have 2 240watt flower panels. Right now I shut them off and just have some CFLs. I didn't want to impede growth anymore. I raised them to 15" or so. I hit them with extra cal-mag also since I heard thats also an issue. Do u have any tips? I have plenty of experience but this is my first real go with LEDs

Although I don't run LED's,I do use perlite,coco and vermiculite. Mix them just about 1/3 each. Maybe a tad more coco in the mix.
The coco offers some organic property to the mix that some of the beneficial bacteria and fungi might take to a little better.
I might be full of crap, but I'm having some fairly amazing results right now. I have used DWC, straight vermiculite, straight perlite, and soil but this mix so far has worked best for me.
My main nemesis growing is heat issues; Mainly caused by a piss poor ventilation system and lack of funds.
Y'all keep up the good work.......J

Even with 30" of separation, I was still having bleaching problems (albeit much, much slower developing) with my 240W Blackstar UV (bloom) light. Thinking to swap the 240W panel for the 180W light, I called Lighthouse Hydro. The gentleman who answered the phone was quite helpful, and spent about 1/2 an hour trying to figure it out the problem. Ultimately, he was at a loss as to the specific cause of these symptoms, but he was insistent that:
--The symptoms I was describing were not light bleaching, but were more likely some kind of deficiency. With their lights, light bleaching takes the form of a slight lightening of the leaves when they come within 6" of the LEDs.
--30" was way too much separation. For the 240W UV, they recommend 12" above the canopy.
--Plants are able to actually touch the light and keep on growing. The only symptoms they've encountered is a slight lightening of the leaves when they grow within 6".
--There's no way my light could be defective.
--The problem could be some weird plant genetics.
--My dealer (Gotham) is usually pretty good about swapping the 240W for the 180W if that's what I really want (he recommended against the swap).
--I should keep trying various combinations until I figured it out. Once I found the solution to the problem, I'd really like the 240W UV. It's their best selling light by far, and it has completed thousands and thousands of successful grows.

After I hung up, I was all set to call Gotham and make the swap, but my mind started chewing on bits and pieces of the conversation. To make a long story short, after days of research and much trial and error (involving the sacrifice of 4 prime clones), I finally zeroed in on iron deficiency as the likely culprit. The exclusivity to new growth only was the tip-off symptom. Once I started adding chelated iron to my nutes, the symptoms began abating, and with one plant, the symptoms have disappeared altogether. The two photos below show a branch of this plant merrily growing within 6" of the light. The burned tips you see is left-over damage from earlier severe iron deficiency. Notice the slight lightening of the leaves in the foreground. I gather this is the real Blackstar light bleaching. Incidentally, those leaves are still growing quite robustly.

Attachment 283525Attachment 283526

So what in the heck is going on here?

After piecing together all my observations and all the results of my experiments, here's my working theory (it's not set in stone so if you have a better explanation I'm all ears). These iron deficiencies appear to be directly related to growth rates. I'm using SensiGrow and SensiBloom which have 0.12% and 0.13% iron respectively. With the growth rates of most all lights out there, this amount of iron is adequate. The 240W Blackstar, however, is so efficient at hitting plants at their chlorophyll-producing wavelengths, that all available iron is quickly drawn into growth, and the plant is unable to suck up enough new iron to prevent deficiency. The insidious aspect of this problem is it takes only a tiny and brief shortage of iron in the growing tips to effectively shut down all growth, and if left untreated, the shutdown will eventually kill the plant (I found this out the hard way on 3 fantastic plants). Making matters worse, recovery is slooow and growth rates never seem to return to their former glory. Although I've never heard of too-fast growth rates causing deficiencies, I have personally experienced too-slow growth rates causing toxicities, so it's not beyond the stretch of plausibility.

Thus, my end goal in all this is to come up with some method of preventing 240W Blackstar "iron shock" in the first place. Right now I'm experimenting with adding iron well before switching lights, and although the results of my experiments are a ways off, it's looking like if this approach works at all it will take between 2% and 5% added iron.

If any of you know of a proven method for preventing Blackstar iron shock, I'd greatly appreciate hearing about it in a post to this thread. If I come up with something, I'll do the same. Thanks in advance. Hataman.

So what did u use? I could try upping the calmag plus dosage

Quote:

---

Originally Posted by Cyclonite

So what did u use? I could try upping the calmag plus dosage

---

I'm using Liquinox Iron & Zinc that I bought at a local nursery. It's 0.2% Iron and 0.2% Zinc. I'm up to 4 oz of Liquinox /gal of diluted nutes so FE is now approx. 1.72% of raw concentrated nutes. I've been prefeeding this extra iron to some clones in my 180W Blackstar veg box, and will transfer them to the 240W Blackstar bloom box in a day or two--keeping my fingers crossed. Also, I just bought some Bonide Liquid Iron Complex which is 5% FE plus a bunch of other micro nutrients. I'll try this if the current Liquinox dosages fail to prevent the problem.

As for the calmag plus, thanks for the offer to help, but none of the symptoms I've experienced look at all like either calcium or magnesium deficiencies. Plus, I originally thought this was a sulfur deficiency so I tried Epsom salt (magnesium sulfate) with no joy. This leaves me about 99% certain this is not a magnesium or sulfur issue, and 96% certain it is not a calcium issue.

On the other hand, all the symptoms I've experienced perfectly fit the description and photos of iron deficiency, and adding the Liquinox Iron is definitely improving things. This has me 99.5% convinced this is an FE deficiency. My remaining questions are primarily how, when, and how much iron to apply. Also, perhaps vegging with a different light setup might solve the problem. Dunno. Weâ??ll see.

I was thinking along the lines of LEDs seem to make the plants need more cal-mag. Also cal-mag has iron in it as well so it could take care of all the issues in the right dose. It also has many other micro nutes the plants need

Thanks for your great work Hataman, Iâ??m going nowhere with thisâ?¦ Your ideas seem right, and symptoms are just what I have.. When it first happened I did think I had a pH problem causing Iron deficiency, but by the time I sorted it the damage was done and they never recovered.

Since I have been extra careful with pH & feeding, and the plants look really great until they get under the flower lights. Then they seem to have a strong burst of growth in the first week and the top leaves start to yellow by 10 days. Iâ??m now trying both flower & veg lights together, and only feeding pH adjusted seaweed.

The latest plant has been under flower for 10 days now and after reading your post I have just given it a shot of Iron (Sequestrene), it shouldnâ??t do any damageâ?¦ Iâ??ll let you know..

Quote:

---

Originally Posted by Hataman

This appears to be a sulfur deficiency.

---

Four of my eight plants looked exactly like this picture. And I recently switched to a new Blackstar 240W uv led. So if it was light bleaching shouldn't all the plants have been affected? Especially if they are taller than the affected plants?

I tried raising the lights. I tried the epsom salts and foliar feeding. Nothing. Started getting worse. In desperation I fed with Miracle Gro (yikes!) and the yellowing stopped. New growth is coming in fully green! Hooray!

I am growing a lowryder mix in forest farm ocean forest soil. I am using 1.3 gallon plastic pots in a 24 x 24 x 60 tent. Two of the eight plants are lowryder2. One shows the yellowing heavily, the other barely so.

Attachment 283562

My latest thinking is that it might be the shock of moving from 18 to 12 hrs and from veg to flower lights at the same time, stressing the plants. They do grow very well initially, but then seem to overstretch themselves and decline.

In my new trial I was going to give a plant 2 weeks of 12 hrs under the veg lights and then move them to flower lights, but things changed and I only managed 1 week, however the buds are as good (better) than original plants that have been under the flowering led for 3 weeks longer! It also did seem a good idea because it evens out the time requirement on both lights.

Unfortunately, I have been changing other things at the same time (just want to get it right!) so no real proof, but may well be worth bearing in mind.

Not sure whether the shot of iron did much good… maybe too late.. but my soil mix was enriched with iron to start with.

I'm happy to report I've got three new plants 12" under the 240W Blackstar Flowering light, and all three are growing in fast track mode. The trick was to give the plants additional iron and let them veg for at least a few hours BEFORE putting them under the 240W. This gave the plants enough time to draw-in the iron and transport it to the growing tips.

The photo below is dated 3/17 22:33. I've nicknamed the four plants in the hempy cups Cannon Fodder Clones #1-4 because they were raised specifically to go up against the 240W Deathstar. At this point, I hadn't yet made the iron deficiency diagnosis so the prospects for these clones was basically certain death. The smaller clone in the lower left is a special case I've nicknamed New Runt for obvious reasons--a perfect candidate for the first sacrifice. The plant in the 2 gallon hempy bucket in the far upper right corner is nicknamed Old Runt. As a cutting, Old Runt started out 1/3rd the size of the next smallest clone in a batch of eight, and went on to outroot and outgrow all of them. All eight clones were severely damaged by iron deficiency. At this point, Old Runt has been sitting in the veg box under the 180W Blackstar veg light for about 2 weeks, recuperating from its bout with the 240W Deathstar (if you look close, you can still significant iron deficiency damage). The big lesson here (that I learned the hard way) is move your least valuable plants under the 240W Deathstar first, then slowly work your way down to your star performers.

Attachment 283626

Below, the photo on the left is dated 3/21 18:30. It shows New Runt one minute before being moved from the 180W Blackstar veg light to the 240W Deathstar for a 12.5 hour light cycle. For the previous three days, it has been fed with SensiGrow and SensiBloom with various concentrations of added iron. The plants in the 1 gallon hempy buckets are Cannon Fodder #1-3. They were transplanted on 3/18, and at that time, Old Runt was fed some iron, heavily pruned to remove damaged leaves, and put back under the 240W Deathstar. The photo on the right is dated 3/24 20:54, and shows the same plant, New Runt, after it has received approx. 39 hours of full-bore exposure to the 240W Deathstar at a distance of 12"--plenty enough to leave a "non-ironed" New Runt a smoking ruin. As you can see, not only has New Runt escaped deficiency damage, but it has also put on considerable new growth.

Attachment 283621Attachment 283622

The photo below is dated 3/24 21:08 and shows the 240W Blackstar flowering light positioned 12" above the canopy. You can see New Runt is positioned center left, Cannon Fodder #3 [Bush Baby] center top, and Cannon Fodder #1 [Darth Maulette] center bottom. Old Runt is top right, and top left is Bonsai Mother. This last plant is a special case. She's a sister clone to Old Runt, and I kept her in her 16oz. hempy cup in an attempt to make a true Bonsai Mother out her. Unfortunately, she grew so fast that I lost the heart to prune her just for the sake of keeping her small. As the 240W Deathstar continued to maul my plants, Bonsai Mother's number came up. Initially I kept her 30" under the light, and she grew just fine with zero damage. After I talked to Lighthouse Hydro, I lowered the light to 18". My rationale was the many days of exposure at 30" might have hardened the plant, and she would now tolerate a shorter distance. Wrong. After just a few hours at 18" she began exhibiting the usual damage. About that time, I began theorizing iron deficiency, so I quick ran out to a local nursery, bought some Liquinox Iron & Zinc, and began feeding Bonsai Mother extra iron. Subsequently I've fed her tons of extra iron, and sprayed her leaves 3-times a night with Bonide Liquid Iron, but as you can see, recovery has been slow, slow. To be fair, though, much of Bonsai Mother's weird, stunted appearance is owing to her still being in a 16oz. hempy cup. Getting back to Bush Baby, center top, she was fed with SensiBloom + Bonide Liquid Iron at 1.5 tsp/gallon for about three days prior to her bout with the 240W. Darth Maulette was fed with SensiGrow + Bonide Liquid Iron at 0.5 tsp/gallon approx. five hours before 240W exposure. At this point, both plants have received about 19 hours exposure to the 240W, plenty enough time to cause the damage, and yet both plants are showing zero damage. Indeed, both appear to growing extremely rapidly. Old Runt also appears to be doing quite well. It must be noted, though, she spent several weeks revegging under the 180W Blackstar, all the considerable deficiency-damaged growth has been pruned away, and the plant has received massive cosmetic LST. In other words, the Old Runt you're seeing in this photo is basically a entire new plant. To quickly summarize, with the 240W Blackstar UV (flowering) light:

Plants with no pre-feeding with extra iron: 100% iron deficiency damage rate.
Plants with extra iron pre-feeding: 100% success rate.

I don't know how it could be any more conclusive.

Attachment 283623

Conclusions:

--The main reason I'm taking all this time to write this post is I wanted to undo any damage I might have caused Lighthouse Hydro and their terrific line of Blackstar LED grow lights. I think I've shown to everyone's satisfaction the 240W Blackstar UV light is definitely not causing light bleaching. I've also proven (to myself, anyway) that Lighthouse's recommendation of a 12" distance (or even less) is indeed accurate. At that distance, my plants appear to be growing in turbo mode. I've gone from blindly accepting this light, to doing mortal combat with it, and now loving it like a trusted horse. I'm definitely keeping it, and I'm also seriously considering buying another to replace my 180W Blackstar HO veg light. I'll have to do some further measurements, but my plants appear to be growing faster with 12 hours of the 240W light than 24 hours of the 180W light.

--The 240W Blackstar UV LED light (and probably all flowering LED panels over 200W) require real growing expertise. They are not beginner lights. The margin for error is a lot slimmer, and users must know their plants AND their nutes like the back of their hands. Here are some of the lessons I learned the hard way. The 240W Blackstar UV light:
*is capable of causing deficiencies by inducing too fast a growth rate (ultimately a really nice problem to have).
*requires users to go over their nutes with a fine-tooth comb and clearly identify those nutrients that will go into deficiency under hyper-growth conditions.
*requires a "pre-feeding" period under a less powerful light. The purpose of this pre-feeding is to get all necessary micro-nutes up into the growing tips of the plant before going under the 240W.
*makes it really hard to rehab plants. Growth pressure is so strong that once plants go into deficiency, they find it extremely difficult if not impossible to catch up. Rehabbing, therefore, should be done under a less powerful light.
*requires that deficiency-susceptible plants be supplied with extra nutes throughout the entire time the plants are under the 240W light.
*for nutrient manufacturers, opens up new market opportunities for hyper-growth LED formulations.
*(if your plants go into deficiency) forces the dilemma of deciding between rehab or starting over. Which is better?

In the photo below (dated 3/7 19:34), the upper right plant is Old Runt rehabbing in the veg box after ~36 hours exposure to the 240W Deathstar. Note how all the damage is occurring in the new growth. This is key to the iron deficiency diagnosis. The center left plant is nicknamed Original Clone. It also is rehabbing after ~8 hours exposure. Note how Original Clone is recovering much faster than Old Runt. So much so, the next day Original Clone was put back under Deathstar while Old Runt was left to veg another two weeks. The lower right plant is a sister clone that has never faced Deathstar. Its turn, however, came up and it eventually had to be put down.
Attachment 283624

The photo below (dated 3/17 20:53) shows Original Clone after nine days of flowering under the Deathstar. This is before I diagnosed the iron deficiency, and note how the damage has carried on. Overall growth is good, but the flowering sites are weirdly diminished.
Attachment 283625

In cutting back Original Clone to expose only the healthy, undamaged flowering sites, the plant suddenly shrank to nothing, and I decided to destroy it.

--This is definitely not a sulfur deficiency. The keys to a correct diagnosis are:
*The damage is contained to new growth.
*Adding sulfur does nothing.
*Adding iron works miracles.

--I wouldn't add CalMag to cure iron deficiency as this raises the risks of introducing calcium and magnesium toxicities. Liquinox Iron and Zinc is 0.2% iron and 0.2% zinc. The problem with this is zinc quickly becomes highly toxic, as I found out when Old Runt suffered mass wilting and necrosis after adding a large dose of Liquinox. Fortunately, a thorough flush quickly restored the plant. In my experience with all this, I've found it's best to stick with the plain, unadorned, base nutes, and only add supplements to treat specific deficiencies. After the Liquinox debacle, I switched to Bonide Liquid Iron Plus Micronutrients. Liquid Iron is 5% iron with much smaller percentages of other micro-nutes. This means I can play around with iron dosages without worrying about introducing other toxicities.

--Thanks redleb for the input. The fact that you're experiencing yellowing 10 days into flower tells me I need to keep adding iron throughout the entire grow.

--HipsterDoofus, interesting tip about Miracle-Gro. Did you use the All-Purpose version? Makes me wonder if it can be adapted for hydro.

--Whew, enough is enough. I'll close by reiterating the 240W Blackstar UV is a great light that definitely does not cause serious light bleaching or photo toxicity. In fact, in the hands of an expert grower, it could well be capable of miracles.

Peace out,
Hataman

Well done Hataman. Apparently there's more to this LED business than meets the eye .. The potential looks really good, if not without risk!

Our grow styles are quite different, so i'll play around until get a reliable method. What I am hoping that the Iron content of my Seaweed additive is enough stop the problem. And still maintaining the lights slightly higher for the time being though.

I'm told foliar feeding is a good way to get Iron in quickly.

Keep charting your progress.

Quote:

---

Originally Posted by Hataman

--HipsterDoofus, interesting tip about Miracle-Gro. Did you use the All-Purpose version? Makes me wonder if it can be adapted for hydro.

---

I did use the all purpose version. And I finally got a good pH meter. My soil is incredibly acidic. The difference is clear between the healthy green ones and the yellow ones. All the healthy plants are around 6.6, the yellow ones are all well below that. So that's my next task, to fix the soil pH.

Attachment 283893
This is what happened to my plant that was under Blackstar 240 veg/clone about 14-16inches above top. Also I had a 600uv in the same room that was sending off some light and this is what happened in 2 days.

Just to update - it really was leaf burn and bleaching on my plants from the led. I moved the plants to natural sunshine for a week and they are recovering nicely. So I've put the blackstar 240w uv back in the box for a while.

Quote:

---

Originally Posted by Hataman

I'm happy to report I've got three new plants 12" under the 240W Blackstar Flowering light, and all three are growing in fast track mode. The trick was to give the plants additional iron and let them veg for at least a few hours BEFORE putting them under the 240W. This gave the plants enough time to draw-in the iron and transport it to the growing tips.

The photo below is dated 3/17 22:33. I've nicknamed the four plants in the hempy cups Cannon Fodder Clones #1-4 because they were raised specifically to go up against the 240W Deathstar. At this point, I hadn't yet made the iron deficiency diagnosis so the prospects for these clones was basically certain death. The smaller clone in the lower left is a special case I've nicknamed New Runt for obvious reasons--a perfect candidate for the first sacrifice. The plant in the 2 gallon hempy bucket in the far upper right corner is nicknamed Old Runt. As a cutting, Old Runt started out 1/3rd the size of the next smallest clone in a batch of eight, and went on to outroot and outgrow all of them. All eight clones were severely damaged by iron deficiency. At this point, Old Runt has been sitting in the veg box under the 180W Blackstar veg light for about 2 weeks, recuperating from its bout with the 240W Deathstar (if you look close, you can still significant iron deficiency damage). The big lesson here (that I learned the hard way) is move your least valuable plants under the 240W Deathstar first, then slowly work your way down to your star performers.

Attachment 283626

Below, the photo on the left is dated 3/21 18:30. It shows New Runt one minute before being moved from the 180W Blackstar veg light to the 240W Deathstar for a 12.5 hour light cycle. For the previous three days, it has been fed with SensiGrow and SensiBloom with various concentrations of added iron. The plants in the 1 gallon hempy buckets are Cannon Fodder #1-3. They were transplanted on 3/18, and at that time, Old Runt was fed some iron, heavily pruned to remove damaged leaves, and put back under the 240W Deathstar. The photo on the right is dated 3/24 20:54, and shows the same plant, New Runt, after it has received approx. 39 hours of full-bore exposure to the 240W Deathstar at a distance of 12"--plenty enough to leave a "non-ironed" New Runt a smoking ruin. As you can see, not only has New Runt escaped deficiency damage, but it has also put on considerable new growth.

Attachment 283621Attachment 283622

The photo below is dated 3/24 21:08 and shows the 240W Blackstar flowering light positioned 12" above the canopy. You can see New Runt is positioned center left, Cannon Fodder #3 [Bush Baby] center top, and Cannon Fodder #1 [Darth Maulette] center bottom. Old Runt is top right, and top left is Bonsai Mother. This last plant is a special case. She's a sister clone to Old Runt, and I kept her in her 16oz. hempy cup in an attempt to make a true Bonsai Mother out her. Unfortunately, she grew so fast that I lost the heart to prune her just for the sake of keeping her small. As the 240W Deathstar continued to maul my plants, Bonsai Mother's number came up. Initially I kept her 30" under the light, and she grew just fine with zero damage. After I talked to Lighthouse Hydro, I lowered the light to 18". My rationale was the many days of exposure at 30" might have hardened the plant, and she would now tolerate a shorter distance. Wrong. After just a few hours at 18" she began exhibiting the usual damage. About that time, I began theorizing iron deficiency, so I quick ran out to a local nursery, bought some Liquinox Iron & Zinc, and began feeding Bonsai Mother extra iron. Subsequently I've fed her tons of extra iron, and sprayed her leaves 3-times a night with Bonide Liquid Iron, but as you can see, recovery has been slow, slow. To be fair, though, much of Bonsai Mother's weird, stunted appearance is owing to her still being in a 16oz. hempy cup. Getting back to Bush Baby, center top, she was fed with SensiBloom + Bonide Liquid Iron at 1.5 tsp/gallon for about three days prior to her bout with the 240W. Darth Maulette was fed with SensiGrow + Bonide Liquid Iron at 0.5 tsp/gallon approx. five hours before 240W exposure. At this point, both plants have received about 19 hours exposure to the 240W, plenty enough time to cause the damage, and yet both plants are showing zero damage. Indeed, both appear to growing extremely rapidly. Old Runt also appears to be doing quite well. It must be noted, though, she spent several weeks revegging under the 180W Blackstar, all the considerable deficiency-damaged growth has been pruned away, and the plant has received massive cosmetic LST. In other words, the Old Runt you're seeing in this photo is basically a entire new plant. To quickly summarize, with the 240W Blackstar UV (flowering) light:

Plants with no pre-feeding with extra iron: 100% iron deficiency damage rate.
Plants with extra iron pre-feeding: 100% success rate.

I don't know how it could be any more conclusive.

Attachment 283623

Conclusions:

--The main reason I'm taking all this time to write this post is I wanted to undo any damage I might have caused Lighthouse Hydro and their terrific line of Blackstar LED grow lights. I think I've shown to everyone's satisfaction the 240W Blackstar UV light is definitely not causing light bleaching. I've also proven (to myself, anyway) that Lighthouse's recommendation of a 12" distance (or even less) is indeed accurate. At that distance, my plants appear to be growing in turbo mode. I've gone from blindly accepting this light, to doing mortal combat with it, and now loving it like a trusted horse. I'm definitely keeping it, and I'm also seriously considering buying another to replace my 180W Blackstar HO veg light. I'll have to do some further measurements, but my plants appear to be growing faster with 12 hours of the 240W light than 24 hours of the 180W light.

--The 240W Blackstar UV LED light (and probably all flowering LED panels over 200W) require real growing expertise. They are not beginner lights. The margin for error is a lot slimmer, and users must know their plants AND their nutes like the back of their hands. Here are some of the lessons I learned the hard way. The 240W Blackstar UV light:
*is capable of causing deficiencies by inducing too fast a growth rate (ultimately a really nice problem to have).
*requires users to go over their nutes with a fine-tooth comb and clearly identify those nutrients that will go into deficiency under hyper-growth conditions.
*requires a "pre-feeding" period under a less powerful light. The purpose of this pre-feeding is to get all necessary micro-nutes up into the growing tips of the plant before going under the 240W.
*makes it really hard to rehab plants. Growth pressure is so strong that once plants go into deficiency, they find it extremely difficult if not impossible to catch up. Rehabbing, therefore, should be done under a less powerful light.
*requires that deficiency-susceptible plants be supplied with extra nutes throughout the entire time the plants are under the 240W light.
*for nutrient manufacturers, opens up new market opportunities for hyper-growth LED formulations.
*(if your plants go into deficiency) forces the dilemma of deciding between rehab or starting over. Which is better?

In the photo below (dated 3/7 19:34), the upper right plant is Old Runt rehabbing in the veg box after ~36 hours exposure to the 240W Deathstar. Note how all the damage is occurring in the new growth. This is key to the iron deficiency diagnosis. The center left plant is nicknamed Original Clone. It also is rehabbing after ~8 hours exposure. Note how Original Clone is recovering much faster than Old Runt. So much so, the next day Original Clone was put back under Deathstar while Old Runt was left to veg another two weeks. The lower right plant is a sister clone that has never faced Deathstar. Its turn, however, came up and it eventually had to be put down.
Attachment 283624

The photo below (dated 3/17 20:53) shows Original Clone after nine days of flowering under the Deathstar. This is before I diagnosed the iron deficiency, and note how the damage has carried on. Overall growth is good, but the flowering sites are weirdly diminished.
Attachment 283625

In cutting back Original Clone to expose only the healthy, undamaged flowering sites, the plant suddenly shrank to nothing, and I decided to destroy it.

--This is definitely not a sulfur deficiency. The keys to a correct diagnosis are:
*The damage is contained to new growth.
*Adding sulfur does nothing.
*Adding iron works miracles.

--I wouldn't add CalMag to cure iron deficiency as this raises the risks of introducing calcium and magnesium toxicities. Liquinox Iron and Zinc is 0.2% iron and 0.2% zinc. The problem with this is zinc quickly becomes highly toxic, as I found out when Old Runt suffered mass wilting and necrosis after adding a large dose of Liquinox. Fortunately, a thorough flush quickly restored the plant. In my experience with all this, I've found it's best to stick with the plain, unadorned, base nutes, and only add supplements to treat specific deficiencies. After the Liquinox debacle, I switched to Bonide Liquid Iron Plus Micronutrients. Liquid Iron is 5% iron with much smaller percentages of other micro-nutes. This means I can play around with iron dosages without worrying about introducing other toxicities.

--Thanks redleb for the input. The fact that you're experiencing yellowing 10 days into flower tells me I need to keep adding iron throughout the entire grow.

--HipsterDoofus, interesting tip about Miracle-Gro. Did you use the All-Purpose version? Makes me wonder if it can be adapted for hydro.

--Whew, enough is enough. I'll close by reiterating the 240W Blackstar UV is a great light that definitely does not cause serious light bleaching or photo toxicity. In fact, in the hands of an expert grower, it could well be capable of miracles.

Peace out,
Hataman

---

I don't get it. I'm having the same problem as always, matches your images perfectly, every plant is hit with it. I moved it them all under a less powerful light and rehabbed. Nothing is changing, I fed with a magnesium/micro mix.. no results, fed with epsom salts, no results, fed with an iron foliar.. same thing. I'm about to dump these for a 400watt hps if something doesn't change.. my clients waiting on his harvest which i should have had by now and is still 8 weeks out

Well, taking a chance here. I built a 4x2x4 cab and have one 240w flower light mounted. good airflow, spacious, poor reflectivity on most surfaces to try and lower the intensity of the light a little.. foliar fed with "spray n grow micronutrient" (5%zinc 10%iron). last time I wasn't using cal mag, so I'm feeding with that as well now in the res.

Have my two hydro girls and a coco I think is likely a male.. but otherwise my 3rd most hardy plant. I would prefer to use some more sacrificial plants.. but these guys are the ones that bounced back quick enough and I need to get a harvest on the way..

starting bloom today, using flora grow, going to use equal amounts of gro, micro, and bloom for the first week and shoot for 6-800ppm on the smaller one, 8-1k for the big girl with the calmag added.

hopefully the shorter light span, (18hr down to 12) the iron feeding, and the calmag will make the difference.. if not the box will accommodate a 400w hps with no trouble..

how often are you foliar feeding the iron?

Well guys, I have some useful information :)
I was using the gh trio, grow bloom and micro. the symptoms here looked a ton like either iron or sulpher def.. so, I checked out the back of the bottles.. grow actually has none of either.. bloom and micro both have micro nutes.. but grow is primarily potassium and a modest amount of nitrogen.

Seeing this, I thought about the Lucas formula.. which uses one part micro to two parts bloom, and cuts out the grow completely.. basically doubling-tripling my iron, and quadrupling my sulpher amounts in the res.
This coupled with a weekly morning foliar feed of iron has completely halted all of my problems.. Not to mention simplified feeding.. Also no longer need calmag.

The only problem with this now is that I don't have a good way of feeding my soil girls, with hydro I am in control.. with the dirt ladies they are more or less on their own. so, next round I think I'm doing hempy buckets with airstones in their res, and using a screen for canopy managment. should be a pretty simple set up
within a day, all of my plants instantly stopped yellowing

A big thanks to Hataman and also the input of Douglas1 ! I have been havnig the same problems as Hataman with my led lights and have been doing similar things to try and solve this problem and already had put my plants in a a recovery light room but didnt have the iron deficiency sussed out until reading this great thread. At the very begging of my troubles i thought iron def may be the problem until all different things started to happen and i sorta forgot about the iron !! Any way, i have 6 plants in different stages of growth and have bought a powder (just containing iron) that i have mixed up at half strength to play it safe. I have watered all plants (just now) and also given a foliar feed which i intend to do every day for a few days. My question is did you have to continue adding to keep the iron to the feed for the rest of the grow or just occasionally or not at ?
The box says that it lasts 2 or 3 months with the one dosage. I am growing in BioBizz light mix and intend to grow in coco the next time around as i believe this will be better for nutrient take up. Many thanks for this thread and any words of wisdom that you have learnt since writing this thread. :thumbsup:

Quote:

---

Originally Posted by mr gold

A big thanks to Hataman and also the input of Douglas1 ! I have been havnig the same problems as Hataman with my led lights and have been doing similar things to try and solve this problem and already had put my plants in a a recovery light room but didnt have the iron deficiency sussed out until reading this great thread. At the very begging of my troubles i thought iron def may be the problem until all different things started to happen and i sorta forgot about the iron !! Any way, i have 6 plants in different stages of growth and have bought a powder (just containing iron) that i have mixed up at half strength to play it safe. I have watered all plants (just now) and also given a foliar feed which i intend to do every day for a few days. My question is did you have to continue adding to keep the iron to the feed for the rest of the grow or just occasionally or not at ?
The box says that it lasts 2 or 3 months with the one dosage. I am growing in BioBizz light mix and intend to grow in coco the next time around as i believe this will be better for nutrient take up. Many thanks for this thread and any words of wisdom that you have learnt since writing this thread. :thumbsup:

---

How did you make out Mr gold after adding the iron? I am having the same issue with 500UV's...lime green on new growth. This started almost instantly...3rd day in.

See the pictures below,

Attachment 289937Attachment 289938