pH Issue or Mg Def? (pics)

ettubrutus

ettubrutus

Well-Known Member
I replaced the batteries in and calibrated my pH meter today and realized I may very well have been off by about .5pH for a few weeks... checking runoff today everything seems to be around 6.7 which is what my goal is... it's a soil grow, organic grow and bloom nutes, h202, and epsom salts once a week... about 2.5 weeks into 12/12...

Weird lower fan leaves, yellow and lots of spots...
 

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MEANGREEN69

MEANGREEN69

Well-Known Member
have you flushed yet? i think i've read somewere that mag def starts from the bottom up...looks like it to me..but i dont know eveything. good luck
 
ettubrutus

ettubrutus

Well-Known Member
smokeybandit22 said:
thats a tricky one. need some pics of leaves that have not gone that far yet.
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I did my first of the scheduled 30day flushes about 3 weeks ago and it seems to pretty much halt the process, but the leaves with the issues just kept going down hill... any of the leaves that havent progressed this far are just normal looking with sporadic blackish gray spots on them... just like the ones in the pictures but no more than 1mm in diameter, the lens on my camera isn't really allowing me to show you... the next flush is on the 9th...
 
smokeybandit22

smokeybandit22

Well-Known Member
ok, I got it. took another look and the random black spots...K deficiency-first the outline edges turns yellow, than necrotic than you get the spotting. with the random spotting on seemingly unaffected leaves as well.
now for the why. seems should be enough in your nutes. given that, your plant is having trouble uptaking K, most likely from high fert salt levels. ur EC is probably off the chart. also, if your soil dries fast and if you are feeding every water or every other water, this will contribute.
flush, than immediately feed. either water, water, feed, water, water feed anf flush once a month or water, feed, water, feed and flush once every 20 days or so.
 
ettubrutus

ettubrutus

Well-Known Member
smokeybandit22 said:
ok, I got it. took another look and the random black spots...K deficiency-first the outline edges turns yellow, than necrotic than you get the spotting. with the random spotting on seemingly unaffected leaves as well.
now for the why. seems should be enough in your nutes. given that, your plant is having trouble uptaking K, most likely from high fert salt levels. ur EC is probably off the chart. also, if your soil dries fast and if you are feeding every water or every other water, this will contribute.
flush, than immediately feed. either water, water, feed, water, water feed anf flush once a month or water, feed, water, feed and flush once every 20 days or so.
Click to expand...
I am going to flush this weekend... I've been doing flush, feed water, water, water, feed, x4, flush... they are looking healthy these days... I think whatever defiency occurred was probably in the first 1 or 2 weeks of veg right when I started to feed them, I guess with the organics I need to be more aggressive right out of the gate... or I suppose my stupid pH pen could be the culprit too... hmmmm :bigjoint:
 
smokeybandit22

smokeybandit22

Well-Known Member
I think you nailed it with the organics plus the feeding being so spaced out. I would prob water, water, feed, water, water feed. being off .5 in soil shouldnt cause too much problems unless it was off on the downside. that defintaely is a k deficiency-the other leaves, mainly the younger ones look healthy and green. plant shouldnt be effected too much but I would consider a non organic nute for the meantime like big bloom or something high in K. you can try some potassium silicate.
 
ettubrutus

ettubrutus

Well-Known Member
smokeybandit22 said:
I think you nailed it with the organics plus the feeding being so spaced out. I would prob water, water, feed, water, water feed. being off .5 in soil shouldnt cause too much problems unless it was off on the downside. that defintaely is a k deficiency-the other leaves, mainly the younger ones look healthy and green. plant shouldnt be effected too much but I would consider a non organic nute for the meantime like big bloom or something high in K. you can try some potassium silicate.
Click to expand...
Yeah it was high if it was anything... 7.2-7.5... my goal has been 6.5-7 hopefully I can get it back down over the next week or so... just dumped the reservoir and started over with fresh water... I just use the reservoir for the fresh water, and then when I do feedings I do it manually... I was waiting every 7 days for feeding, I suppose I'll do it every 5 days from here on out...

I've been doing a double dose of Earth Juice Grow and Bloom... they aren't stretching anymore so I'm going to taper off the grow this week...
 
smokeybandit22

smokeybandit22

Well-Known Member
yeah those are some stretchy motherfkrs-sounds like u r on top of it-good work. do taper off the grow slowly and if u havent taken clones yet, now would probably be the latest u would want to take them. plant can accept tolerances of up to a 1.00% for a few days before issues start.
controlled stretching is what you want-and seems to be what you got- if ur lighting is sufficient than they are gonna produce around 2-2.5 zips each, given no issues arise. for the plant, it is normal to use alot of extra k during the first three weeks. that's why u will see alot of posts about one's leaves yellowing rapidly in the first weeks of flowering, most assume, and myself sometimes as well in the past, assume it is a N deficiency when it really is K, maybe slightly N in there too.
if these are ur gals and gonna keep and clone and grow again than u really need to pick up some pottassium silicate-look @ grotek.
I would ditch the epsom salts at this point, seeing that ur plants are not going to like the high EC or salinity concentrations. I would replace that with some hydrated lime mixed into the top layer of your soil. will really help provide the extra mg and ca along with buffering the ph. without increasing the EC concentration so much. 6.5-7.5 you should be fine.
this link is resourceful and helpful to understand the basic biochemistry of mj
http://www.drugs-forum.com/growfaq/1534.htm

post up some more pics-now is the most crucial time in mj's life- it will determine ur final yield and overall health. late flower is easy, veg is easier, first 3 weeks of 12/12-critically important and easy if u know what to look for
 
ettubrutus

ettubrutus

Well-Known Member
smokeybandit22 said:
post up some more pics-now is the most crucial time in mj's life- it will determine ur final yield and overall health. late flower is easy, veg is easier, first 3 weeks of 12/12-critically important and easy if u know what to look for
Click to expand...
Here they are... overall mostly gorgeous... the last pic is my g-13 Haze girl... I can't wait :) :bigjoint:
 

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ettubrutus

ettubrutus

Well-Known Member
smokeybandit22 said:
looking good. looks like u may have a little burn from chlorine so I would let my tap sit for 24-48 hours if not doing so already
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Thanks for your help... you're right about the chlorine burn, it's from the flushes, I don't have anywhere to store 18 gallons of water to evaporate before the flushes :(

Everything in the reservoir sits for at least a day before it's used...
 
ettubrutus

ettubrutus

Well-Known Member
ettubrutus said:
Thanks for your help... you're right about the chlorine burn, it's from the flushes, I don't have anywhere to store 18 gallons of water to evaporate before the flushes :(

Everything in the reservoir sits for at least a day before it's used...
Click to expand...
You know of any organic chlorine neutralizer?
 
smokeybandit22

smokeybandit22

Well-Known Member
no, but if you let it sit, u should be ok. you can add an air stone to boost up the o2 levels and speed evap of the chlorine. plants do need some amounts of Chlorine.
 
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