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. Weā??ll see.
Hataman Reviewed by Hataman on . 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, Rating: 5