Plant (Leaf) Nute Deficiency Problems?

[kingkola1]

I could use some help identifying this issue... These pics are from two of my largest of 8 plants and are the only ones that exhibit this leaf problem and only on the lower leaves (not on new growth). The blotches look almost like a shiny metallic bronze color which was hard to capture in the photos. I am growing in 1/3 coco, 1/3 perlite, 1/3 Ocean Farms potting soil. I have been using 50% of the recommended Emerald Harvest nutes until the last feeding where I planned to move it up to 75% for their Early Veg feeding schedule. I use RO water with 100% of the recommended Emerald Harvest Cal-Mag (5ml/gal) for watering and feeding as I have always done. I increased the feeding amount to try to get better yields. The last grow yielded nicely though at .51 grams per watt under my 1000W MH bulb. It sort of looks like a Phosphorous deficiency but none of the other 6 plants exhibit this. In the Phosphorous literature I read said cramped roots could create this deficiency. These plants are ready to be transplanted out of their 1/2 gallon grow bag to my larger 5 gallon pots but was waiting a bit for the others to catch up in size. I may transplant them in the next day or two. They are about 24 days old since the seeds popped. They did not show these signs at all until 24 hours after yesterdays feeding at 75% concentration. The pH going in yesterday was 6.0 and the drain to waste run off was 6.4. My previous grow (my first one) had no nute or bug issues to report.

Other than that, I don't really have any other plant issues. Any advice from all of you experts out there on how to fix this before it becomes a big problem?

[NebulaHaze]

Have you done a thorough inspection all over the plant and under the leaves and in the soil for any signs of bugs?

I looks a little like a Calcium deficiency, and using RO water is a common trigger for Calcium deficiencies, but you're already using a Cal-Mag supplement so it seems unlike that the plant just wants higher levels of Calcium. It's great you're checking the pH, and it seems to be in the 6-7 range going in and out, which is good.

It is something to consider that you upped the nutrients levels and immediately saw these symptoms, but honestly they don't really look like the symptoms of too much nutrients (which usually gives you nutrient burn) and it could possibly be a coincidence. However, sometimes giving too much of one nutrient can cause lockouts of other nutrients, and it's definitely possible to get the signs of a nutrient deficiency because a plant is rootbound.

However, it looks like your plant is in a smart pot (fabric pot) which makes it a lot less likely that it's rootbound, because the air from the sides actually prunes the roots so they don't circle around the pot. Has anything else changed like moving the light closer? How well is this plant drinking compared to the others? What's the temperature/humidity in there?

It's really frustrating when it's just one plant showing symptoms, and the others are fine. But honestly overall it looks pretty good!

[oldjarhead100]

Nebula says it all I would ask if all the plants are the same strain sometimes when I grow more than one strain at a time I get nute issues, I would transplant them and see what happens good luck