Sick plant, any help would be great !

[OGK10]

Dinafem - Critical Cheese,
5 weeks 5 days into flower,
11hours on 13 off,
Day temp 23-25c Night temp 16-18c, Humidity 40-50,
Ph of water and soil is always 6.5,
Watered with 3l every 3-4 days,
Biobizz lightmix in 10l fabric pots,
I use biobizz grow/bloom to their nute chart for lightmix, molasses & a bit of AN Sensizym every other watering, problem started about a week and a half ago, thought it was cal or mag deficiency so i ordered biobizz calmag, they've had 2 waterings with the recommended dose, I haven't noticed any other of the good leaves being attacked yet but the affected leaves have just carried on getting worse, is that normal ?
Any other idea's of what it could be ?
And should these get through to harvest with the green they have left ?
Thanks in advance

 

[Dr.B]

You're right it looks like a calcium deficiency but I wonder if those plants have fans pointed directly at them. Could be a wind issue...

 

[mysticepipedon]

The lower leaves that have the brown spots on them will never "heal," even when you fix the deficiency. If the next leaves up don't get brown spots, you were successful.

You might just remove the affected leaves so it's easier to see if the newer ones are also being affected.

 

[OGK10]

You're right it looks like a calcium deficiency but I wonder if those plants have fans pointed directly at them. Could be a wind issue...

Ive got two fans that blow over the tops and one thats blowing under the canopy, so i wouldn't think its a wind issue, just hoping my feeds with the cal/mag will stop any newer leaves going to shit, thanks for the input

 

[OGK10]

The lower leaves that have the brown spots on them will never "heal," even when you fix the deficiency. If the next leaves up don't get brown spots, you were successful.

You might just remove the affected leaves so it's easier to see if the newer ones are also being affected.

Ahh nice one mate, was hoping it was just that, I've taken a load of good pics today so I'll compare in a few days, hopefully doesn't get any worse, I'll leave the leaves till they're completely dead let the plant use up whatever's in them, thanks

 

[Dr.B]

Ive got two fans that blow over the tops and one thats blowing under the canopy, so i wouldn't think its a wind issue, just hoping my feeds with the cal/mag will stop any newer leaves going to shit, thanks for the input

No worries. If the fans up to blow in fixed directions it could be causing the problem. It looks like most of the damage is on the tops.... I made a similar revelation recently after moving into a new tent. Fans were not as carefully directed as they previously were. It affected the tops, in the strongest light, and it manifested as a calcium issue. Upping the calmag only caused nutrient burn but redirecting the airflow fixed the problem immediately. Easy fix. Good luck to you.

 

[OGK10]

No worries. If the fans up to blow in fixed directions it could be causing the problem. It looks like most of the damage is on the tops.... I made a similar revelation recently after moving into a new tent. Fans were not as carefully directed as they previously were. It affected the tops, in the strongest light, and it manifested as a calcium issue. Upping the calmag only caused nutrient burn but redirecting the airflow fixed the problem immediately. Easy fix. Good luck to you.

They're all oscillating fans and nah its pretty much here and there from the bottom to top mate and mainly the fan leaves but ill try moving them up an inch or so see if that helps at all, thanks

 

[chemistry]

You need to feed and water more than once every three to four days, your in flower, so your plant are rampant for flower nuits in week 5.

 

[OGK10]

You need to feed and water more than once every three to four days, your in flower, so your plant are rampant for flower nuits in week 5.

I'm giving them full dose of feed every watering as advised by biobizz and im literally watering them when they need it any sooner ill drown the roots any later the soil would get too dry but you're right i might need to up my feed, thanks

 

[SntWick]

Here’s some charts

 

[OGK10]

Here’s some charts

Yeah mate thats what i used and got me thinking it definitely looks like magnesium def, so i added cal/mag to the mix and I'm going to up my feed as i reckon i have a slight nitrogen def too, just been to check on them and I'm alot less worried today as it seems to be the leaves that were already affected by the deficiency, thanks

 

[SntWick]

Yeah mate thats what i used and got me thinking it definitely looks like magnesium def, so i added cal/mag to the mix and I'm going to up my feed as i reckon i have a slight nitrogen def too, just been to check on them and I'm alot less worried today as it seems to be the leaves that were already affected by the deficiency, thanks

Magnesium is a source of plant energy. Dissolve some magnesium sulphate in water and foliar feed it. Or even can water straight into medium. It’s pretty fast acting you can see the diff

 

[OGK10]

Magnesium is a source of plant energy. Dissolve some magnesium sulphate in water and foliar feed it. Or even can water straight into medium. It’s pretty fast acting you can see the diff

Yeah I've given them 2 foliar feeds of cal/mag as well as adding it to my feed since i noticed it, seems to have sorted it, should be able to tell wether it has or not in the next 3-4 days hopefully