Help! Leaves Turning Yellow And Burnt Brown!

[Sdiegofuego]

have 5 plants 2 different strains, all in soil in 1g pots in their 4th week of vegetative stage. I've been seeing some leaves look really bad. Some are cracking and have small holes in them, while others are turning yellow then brown and crispy. One fan leave on the lower branches fell off today. Here are some pics.


Room temp is 72-82F

RHumidity at 54%

18/6 light cycle

Feed ph water of 6.3-6.5

Feed mutes every 3rd watering with fox farm trio at half strength and 2ml of cal mag.

Reservoir is aerated and is ph.8.8 before I add anything to it.

Soil run off water comes out 6.3-6.5 ph / with about a 6 EC


From google, I think it might be calciumdefinciency or possibly boron or manganese?

 

[Juicebox]

The one at the bottom that yellowed up is pretty normal throughout the grow....looks like somthing been munching on them leaves....did you top or fim that plant at anytime?

 

[GanjaNGains]

View attachment 694945 View attachment 694943 View attachment 694944 View attachment 694942 View attachment 694941 View attachment 694940 have 5 plants 2 different strains, all in soil in 1g pots in their 4th week of vegetative stage. I've been seeing some leaves look really bad. Some are cracking and have small holes in them, while others are turning yellow then brown and crispy. One fan leave on the lower branches fell off today. Here are some pics.


Room temp is 72-82F

RHumidity at 54%

18/6 light cycle

Feed ph water of 6.3-6.5

Feed mutes every 3rd watering with fox farm trio at half strength and 2ml of cal mag.

Reservoir is aerated and is ph.8.8 before I add anything to it.

Soil run off water comes out 6.3-6.5 ph / with about a 6 EC


From google, I think it might be calciumdefinciency or possibly boron or manganese?

Try giving some extra cal mag wouldn't hurt no worries my friend still have plenty of time to figure it out the bottom leaf that looks completely yellow and fell off is prob just due to not getting enough light those bottoms leaves tend to do that and honestly you will prob just end up pulling those leaves eventually anyways. Also the brown spots in the middle of the leaf make it look like a magneses issue so up the cal mag and be patient :)

 

[Snoopdog6502]

Use the cal mag and id give it a shot of bloom food next feeding, the wrinkly defored leaves kind of looks like low potassium. Vegging plants need phosphorus and potassium too. Lots of feeding schedules neglect that.

The bottom leaf, yank it off. :D its done.

 

[Sdiegofuego]

The one at the bottom that yellowed up is pretty normal throughout the grow....looks like somthing been munching on them leaves....did you top or fim that plant at anytime?

Yes I topped 3 and fim 2 others! I checked for any insects on the leaves but I couldn't find anything?

 

[Tank707]

Don't stress on that little yellow guy. Pluck him and any other leaves under the canopy. Your baby will thank you with a growth spurt

 

[Juicebox]

Ahh

Yes I topped 3 and fim 2 others! I checked for any insects on the leaves but I couldn't find anything?

Ahh thats why she looks munched on its from the fim is my guess

 

[Dutch Jon]

Reservoir is aerated and is ph.8.8 before I add anything to it.

Soil run off water comes out 6.3-6.5 ph / with about a 6 EC

I assume your pHing around 6.5 for soil but 6 EC? Wow
But looks like what you suspect (manganese deficiency) to me, I'd check the calibration on your pH pen, brown/yellow started at the base of the leaves, ilregular growth . . has the growth slowed down?

Away someshow confirm your pH, then maybe concider if it needs flushing because the 6 EC

Edit: the 8.8 initial water pH and if your pHing down to 63-6.5 most pH down are phosphoric acid that amount might be enough to some sort of ataganist for manganese

 

[Sdiegofuego]

I assume your pHing around 6.5 for soil but 6 EC? Wow
But looks like what you suspect (manganese deficiency) to me, I'd check the calibration on your pH pen, brown/yellow started at the base of the leaves, ilregular growth . . has the growth slowed down?

Away someshow confirm your pH, then maybe concider if it needs flushing because the 6 EC

Edit: the 8.8 initial water pH and if your pHing down to 63-6.5 most pH down are phosphoric acid that amount might be enough to some sort of ataganist for manganese

Ph pen is calibrated. And I made a mistake, my run off was about 3.0 D.C. and yes they are having slow growth

 

[Dutch Jon]

"...my run off was about 3.0 D.C. and yes they are having slow growth

Yes, still signs are pointing to manganese dif. like you initially suspected (props)
I'm not trying to be an know it all but 3.EC is a bit high IMO . . even though regardless you have nearly classic sign of Mn deficiencies no other condition starts from the stem out like that. I believe you that your adding 1/2 strength nutes, so your 8.8 pH water is causing you to add so much Phosphoric acid(pH diwn) that is causing a degree of P. Toxicity which locks out your Mn. also between your the minerals in your water source and the high phosphoric acid causing higher than normal pH and lockout in general. Below is a mineral wheel, that explains how Phosphorus is a ataganist to Mn.

The only salution I can think of is flush you your plants and change your water source so you don't have to add all that pH down.

If you follow the arrow from P. to Mn you'll see the opposing arrows indicating the high Phosphorus is an ataganist to Manganese

 

[Dutch Jon]

Above I wrote 'higher than normal pH'

meant 'higher than normal EC'

 

[Sdiegofuego]

Yes, still signs are pointing to manganese dif. like you initially suspected (props)
I'm not trying to be an know it all but 3.EC is a bit high IMO . . even though regardless you have nearly classic sign of Mn deficiencies no other condition starts from the stem out like that. I believe you that your adding 1/2 strength nutes, so your 8.8 pH water is causing you to add so much Phosphoric acid(pH diwn) that is causing a degree of P. Toxicity which locks out your Mn. also between your the minerals in your water source and the high phosphoric acid causing higher than normal pH and lockout in general. Below is a mineral wheel, that explains how Phosphorus is a ataganist to Mn.

The only salution I can think of is flush you your plants and change your water source so you don't have to add all that pH down.

If you follow the arrow from P. to Mn you'll see the opposing arrows indicating the high Phosphorus is an ataganist to Manganese
View attachment 695831

Thank you so much for he info! Helped a lot! I'm going to change to RO/DI water and flush on their next watering before I transplant! I'll keep y'all posted