name that deficiency!! seriously tho... name it..

[guyonthecouch]

17 days into flower. System is a 6 site UC, water chilled to 66, day temps 79f - 64% humidity, night temps 70f - 50% humidity. RO water, 90 PPM going into system.

nute mix per gallon: 1 ml Zone, 2 ml calmag, 4ml H&G A and B, 2.5 ml Crystal Burst (it's really comparable to Ginormous but a bit cheaper). I also added a total of 3 Tbs of epsom salt to the system which is 55 gallons. Total PPM is 540.

Girls have been drinking pretty consistently at a total PPM of 540 and I let ph swing from 5.4-ish to 6.2-ish. Roots look great. So here's the deal, they were looking good then about a week ago, they started showing a little mag def in the newer shoots and I gave them another shot of epsom at 1 Tbs total. Within a day, they weren't "praying for mag anymore, but I started to notice some of the older growth on a few of the plants started showing yellow veins while the rest of the leaf stayed a lush green, also with stem purpling. As that progressed, it turned into the entire affected leaves turning yellow. Is this even a deficiency? Some leaves also show some burnt tips so I don't know. They aren't taking down more water than food I hesitant to push the PPMs higher in the UC unless I'm sure they are actually needing a hotter mix. Does this look like they are hungry for nitrogen? possibly a P def?? here's some pics:

 

[devilsshare]

Clean out system flush for a day then add just ur AB and calmag cut out everything else. Keep ppms low. Alot of the time a toxicity with show same signs as deficiency. Add more AB as u go. Only add a little bit of additives but id wait until wk 4 or 5 when they start wanting more PK. Less is more.

 

[another_sellout]

Yellowing of the veins (veinal chlorosis) is caused by a lack of iron, either because it's deficient or locked out due to an excess of potassium, magnesium, sulfur or copper. So I'm told.

This may help:
http://www.marijuanapassion.com/forum/showthread.php?t=54233

But maybe you're just running nutrients that just don't agree with one another. Different companies run different base ingredients, and they can cause conflict. Flush with a very mild, 25%, base nutrient mix. Flushing with plain water may deny the plant what it needs to move other problems out of it's system. Make things mild and see if the ppm in your reservoir goes up. If it does, you're pulling out your wastes and salts well. Try using just one line of product until things get stable, then work up to your normal levels and add only one or two of your amendments one at a time.

Also, that's an awful lot of epsom salt, especially considering you already added CalMag. Epsom is magnesium sulfate, and is already a base ingredient in CalMag. I'd cut that out until you saw yellow between the veins on the leaf, not in the veins. It may be the cause of your confusing lock out as well.

Hope that helps at all. Good luck.