Is this Magnesium deficiency?

[Cerul]

Hi guys,

This is a feminized Screamberries (Scream F1 x Hot Glue by SoFem Genetics). Its about 35 days old in a 7 gallon pot with Roots organic soil and under a Mars Hydro 300W led. I started watering with dechlorinated tap water and FloraNova at 1/4 mfg. recommended strength. The large fan leaves show these lighter marks which started 10 days ago. I looked through the infirmary forum pics and think that it may resemble a Mg deficiency. Am i right?
I hope this is not a serious problem and is reversible.
Thanks!

 

[radguyjohn]

Hard to say for certain with the blurple on; I have the same issue on larger fan leaves but it goes away gradually so I think it could be a byproduct of explosive growth. I upped calmag by a hair but time could've also straightened it out.

Good luck!

 

[Cerul]

Thanks @radguyjohn!!
That is certainly encouraging!

 

[Mañ'O'Green]

I have seen in rare occasion a calcium deficiency can also look like that. I think you should be using FloraNova Grow at this stage of the plants growth? Environmental factors can also be in play here:

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! Turn off the grow lights.

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(copy and paste)-->

Problem:

Medium/grow method:

Feed: and supplements used:

water source:

PH in the root zone:

Strain/age:

light used:

Climate:

Additional info: