Need help with diagnosing

[Jamk911]

I have yet to find anyone who knows exactly whats wrong here.. if possible could someone please te me whats wrong with this plant and how to correct it.. I thought it may be nute burn.. and flushed since it happened right after heavy nutrients and watering.. but now not soo sure.. this plant has went from fine to this in less than 3 days. Thank you

 

[Mañ'O'Green]

I will move this to the infirmary.

Please fill in this form: (copy and paste part is below, this first one tell what specifically to include)

-Problem: (brief description)
-Medium/grow method: soil; soilless-- coco, or peat based like Promix, etc. (please provide the actual product name); DWC, NFT, etc.
-Feed and supplements used: include brand, dosage/strength, frequency of feeding and watering (alone); method-- by hand, drippers, rercirc' or drain-to-waste,... N-P-K #'s too if you can!
-Water source: RO/DI; tap- dechlorinated-?..... EC or TDS reading; pH (don't bother with this on RO/DI, do bother with TDS/EC though to confirm it's working well enough)
-Strain and age
-Climate: night and day ambient T and RH%; res' temperatures; any extremes in T/RH% exposure
- Light used: HID, LED, COB, combo of,... wattage; light cycle hours (20/4, 18/6 , etc.); distance to tops....
-Additional info: PH in the root zone. How long have the plants been affected?...How fast did symptoms appear?... Anything else you think might be relevant..

--Pictures including WHOLE PLANT PICS, and troubled leaves.. use normal light or flash as other light sources ruin color rendering, critical for diagnostics!

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(copy and paste)-->

Problem:

Medium/grow method:

Feed: and supplements used:

water source:

Strain/age:

light used:

Climate:

Additional info:

 

[Jamk911]

Medium: jiffy seedling mix

Lighting: 600w neillo cob LED 15in away 20 on 4 off

Feeding: water whenever needs . Fingers w knuckles dry... gave nutrients day this started though.. for first time some 24 8 16 random plant fertilizer


Water: tap water.. idk anything otherwise..

Climate: between 70 and 80 always just 2 plants and a fan in a closet

Strain: its a bag seed soo idk.

 

[Proph]

Medium: jiffy seedling mix

Lighting: 600w neillo cob LED 15in away 20 on 4 off

Feeding: water whenever needs . Fingers w knuckles dry... gave nutrients day this started though.. for first time some 24 8 16 random plant fertilizer


Water: tap water.. idk anything otherwise..

Climate: between 70 and 80 always just 2 plants and a fan in a closet

Strain: its a bag seed soo idk.

What is the ph of the water you use? Seedling mix is not something you want to use to grow a cannabis plant from seed to harvest. There is no real food/nutrients in it. So it could be a true magnesium deficiency or it could be caused by a ph lock out.