Phosporous Deficiency?

[Boradan]

It's not you, I'm a confusing bastard. I try to say things normal, but the science data just finds it way in there.

 

[Yoop906]

Light: 2 x Viparspectra 600W reflectors (one on each plant @ 18")

The issue is mainly on top growth, with a few lower leaves showing a few spots forming.
I raised the light a few inches in case it was stressing them, but no Light burn at the minute)

I'm a rookie (fair warning). But that is a lot of light for each plant isn't it? I had similar issues just the other day and read a piece on how LED lights with too much intensity will cause phosphorus deficiencies - that article is tied to another forum so I don't think it would be kosher for me to post it here. I was using five 300w generic LED lights on 6 plants in a 4x4 tent and I swear I could see the phosphorus deficiency symptoms in the light overlap areas which would have been higher intensity. But again, I'm a rookie.

 

[Boradan]

I'm a rookie (fair warning). But that is a lot of light for each plant isn't it? I had similar issues just the other day and read a piece on how LED lights with too much intensity will cause phosphorus deficiencies - that article is tied to another forum so I don't think it would be kosher for me to post it here. I was using five 300w generic LED lights on 6 plants in a 4x4 tent and I swear I could see the phosphorus deficiency symptoms in the light overlap areas which would have been higher intensity. But again, I'm a rookie.

I already raised the height of the lights, so that should help if the lights are part of the problem.
Feel free to pm me the article if you don't want to post the link here.
To be honest though, I think its more of a pH issue, since I have maintained the same height for the lights throughout the grow, and the issue only happened recently with a pH rise.

 

[Master_gRoshi]

I already raised the height of the lights, so that should help if the lights are part of the problem.
Feel free to pm me the article if you don't want to post the link here.
To be honest though, I think its more of a pH issue, since I have maintained the same height for the lights throughout the grow, and the issue only happened recently with a pH rise.

I have exact same looking issue been battling since veg. My ph stays at 5.8 lol. Im at a loss.
Was told its possibly a fungus
And also now think possibly too much led? Lol is that even possible?
@Rev. Green Genes you hear of led causing lock outs or defs? I been pumping wattages per plant lol.

 

[Waira]

Borodan-- I think this is a micronute defc. mate, though P isn't totally out,... somewhat confusing symptoms with the pretty consistent interveinal necrosis on fans up that high; this is where immobile nute defc.'s hit first and worst typically, and these could pass for B or Mn defc.,..... most of the micro's are immobile, P is fully mobile,.. but I do see P defc., (fan tapping of it up) higher than is usually associated with this defc.,....
your pH, did you get a sudden shift? Even at 6.0, B and Mn are getting thready for availability, they do better at lower pH,... margins are already thin on these!

*fixed!* >>>> there is a chance this is a weird Ca defc.. a serious collapse from the lights maybe, pH drift, or both,.. Ca is also poorly mobile, but the larger dead patches don't fit it well,..... now that I think of it, that pic of the purple shorter leaf bud, that looks a lot more like Ca defc., finer spotting, rusty color, hitting along the mid-rib/veins,...
might be time to get some dedicated micronutes, like Earth Juice Microblast, and lower that pH below 6.0.....:smoking:

 

[Boradan]

Borodan-- I think this is a micronute defc. mate, though P isn't totally out,... somewhat confusing symptoms with the pretty consistent interveinal necrosis up on fans that high; this is where immobile nute defc.'s hit first and worst typically, and these could pass for B or Mn defc.,..... most of the micro's are immobile, P is fully mobile,.. but I do see P defc., (fan tapping of it up) higher than is usually associated with this defc.,....
your pH, did you get a sudden shift? Even at 6.0, B and Mn are getting thready for availability, they do better at lower pH,... margins are already thin on these! View attachment 862138 >>>> there is a chance this is a weird Ca defc.. a serious collapse from the lights maybe, pH drift, or both,.. Ca is also poorly mobile, but the larger dead patches don't fit it well,..... now that I think of it, that pic of the purple shorter leaf bud, that looks a lot more like Ca defc., finer spotting, rusty color, hitting along the mid-rib/veins,...
might be time to get some dedicated micronutes, like Earth Juice Microblast, and lower that pH below 6.0.....:smoking:

Yes to the sudden pH shift.
Due to me living in the back-end of nowhere, it takes almost a week for shizz to get here.
A few weeks ago, I - lets just say I 'ran out' of pH down and had to use Lemon Juice on a daily basis until the replacement pH down got here - took about 5-6 days for it to arrive.
During that time the pH fluctuated pretty wildly between 5.8 and 6.8 daily...
I have NO idea why that totally slipped my damned mind in the original post.
I now have the pH at 5.8.

Also, that chart is for Soil. I am running in a DWC system if that makes a difference to your thinking.

 

[Rev. Green Genes]

I have exact same looking issue been battling since veg. My ph stays at 5.8 lol. Im at a loss.
Was told its possibly a fungus
And also now think possibly too much led? Lol is that even possible?
@Rev. Green Genes you hear of led causing lock outs or defs? I been pumping wattages per plant lol.

I have heard that COB's in particular are causing cal/mag issues in some plants. But it does not appear to be fully understood either. It doesn't make sense physiologically speaking, but either does UV causing more trichs. I have not seen this happen on any of my plants, but I'm getting COB's soon, we shall see.

 

[Rev. Green Genes]

here's a chart for hydro, it is different.

 

[Master_gRoshi]

here's a chart for hydro, it is different.

View attachment 862214

This chart makes me angry lol. Im right in the optimum sweet zone. Oh well

 

[Dabber]

I'm also a newbie growing in soil but I have the same spots on 1 of my BB Kush I took it as a sign of Cal Mag / Phosphorus and I hit it with a dose of Cal Mag and 2 grams MEGA CROP per gallon and stopped it dead in it's tracks the spots have been there for about 2 weeks with no change. Good luck