All of my plants are turning yellow from the top

[madalasatori]

This has been happening slowly for the last month.

About a month ago I used a fortefog smoke bomb in the room following an infestation of thrips.

the plants are fed from the bottom using capillary matting.

it seems to be affecting the older plants rather than the young ones - the ones that weren’t present when the smoke bomb hit seem to be doing better but that could just be because they are young.

I’ve not added anything else to the room but the symptoms Look a lot like off gassing.

Could it be the smoke particles have somehow got into the capillary matting and are poisoning the plants?

Or more likely a pest?

please help, I’ve got some beautiful mums that I would be devestated to lose.

 

[madalasatori]

[No message]

 

[troutman]

Just made this post about the same issue basically.

Get cal/mag.

https://www.icmag.com/forum/marijuan...s#post17921726

Note: Check for pests anyway. Maybe, some are still around.

 

[Creeperpark]

Its not from off gassing. You need to do a pour through and collect some run-off and test it. The bigger plants are showing more problems because they need a fix the most. What kind of soil and water are you using?

 

[Creeperpark]

You have a nutrient imbalance due to causes in the substrate. If you are having to set off fortefog smoke bombs in your grow, I would say you have something wrong, what ever it may be. . Thrips or any bug infestation starts with sick plants that have an imbalance in the ecosystem.

 

[GMT]

Take some cutting the way you would do rose cuttings just in case. You know snip the bottom and the tops off each and put them somewhere else. Then you can try to fix it without too much stress.

 

[madalasatori]

Thanks all for the contributions. I was indeed having PH lockout from PH being too low. I’ve ran the same set up for years without a hitch so never every thought to look there. Am feeling rather embarrassed to have made this thread tbh but am glad I got to the bottom of it. I had to run 30 litres of plain water through each 3 litre pot before the run off came out at 6.0. I do however suspect the smoke bomb contributed in part to the low PH as I remember a similar thing in another room a few years ago following a smoke bombing.

thanks again icers, plants are now showing signs of recovery

 

[Cuddles]

just a side note from the sidelines: pH problems can be fixed easily when you have a water ionizer