Another yellowing plant problem. Please help

I'm growing 5 plants in a greenroom 4x4 tent. plants are white widow clones in coco medium in 15lt autopots under a 600w lamp. air exchange is very good temps always between 24-28 humidity also good.I'm using canna nuts and sticking religously to the canna grow guide nuts schedule. I'm 2 weeks into flower and in the last week all my leaves have started to turned yellow. this is not my first grow but my first for a number of years and my first in a tent. I'm in a soft water area and I'm very meticulous on my PH levels which is always 6.4 in my nuts res. up until the last week or so my girls looked in perfect shape & healthy but as each day has gone by this week they just seem to be getting worse. I have stopped all nuts and they have been on just water for the last 3 days PH 6.4.From reading previous threads on here it seems to be a common problem and there seems to be so many differing opinions. can anyone help PLEASE

Idk jack about your nutes, but have you cut off nitrogen completely? How often are you watering?

UncleReemis said:

Idk jack about your nutes, but have you cut off nitrogen completely? How often are you watering?

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my nuts are canna
http://www.canna-uk.com/

i have cut nothing off nitrogen wise and the autopots are a feed on demand system from a 50lt tank which is emptied and cleaned and re-filled with fresh water and nuts every week.

would adding cal/mag help ?

If your base nutes don't have Ca and Mg then yeah, you should have added it a long time ago.
The leaves that are largely yellowing and dieing are lower leaves, correct? This is more of a light issue and a natural process.
I don't see much yellowing towards the tops.
Also your pH might be a tad high.

UncleReemis said:

If your base nutes don't have Ca and Mg then yeah, you should have added it a long time ago.
The leaves that are largely yellowing and dieing are lower leaves, correct? This is more of a light issue and a natural process.
I don't see much yellowing towards the tops.
Also your pH might be a tad high.

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Canna A+B should have a Ca & mg in it. ?? yellow leaves are all over the plants and one plant is nearly completely all yellow leaves. what light issue do you think it could be. isnt PH 6.4 within the ideal range (6.2-6.6)

the more I'v read the more i'm thinking its a nitrogen def

It looks like a nitrogen def, but I consider that to be uncommon during flowering. But perhaps it is.

UncleReemis said:

It looks like a nitrogen def, but I consider that to be uncommon during flowering. But perhaps it is.

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do you think I should try some
Nitrogen Deficiency Nutrient next ?

roystonvassy said:

do you think I should try some
Nitrogen Deficiency Nutrient next ?

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Sure, just stay conservative and start out small. If it get's a little better, you know you're on the right track. Best of luck mate

UncleReemis said:

Sure, just stay conservative and start out small. If it get's a little better, you know you're on the right track. Best of luck mate

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thanks for the advice

I agree with Uncle. Kinda like, take two aspirins and see in the morning.... although in this case, it may take a little longer before your baby starts feeling better.

Check the progress and if the problem persists, come back for another office visit. But I think that should fix the problem.

Good luck!

cheers

ghgou812 said:

I agree with Uncle. Kinda like, take two aspirins and see in the morning.... although in this case, it may take a little longer before your baby starts feeling better.

Check the progress and if the problem persists, come back for another office visit. But I think that should fix the problem.

Good luck!

cheers

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will do