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Help for a "mystery"

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frankthirtyspears
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Help for a "mystery"

Post by frankthirtyspears »

Food evening guys, here with another question, this time about a "mystery" I've been trying figuring out in the last few days...

I've got three autos, in canna soil, BioBizz Nutrients, 150w MarsHydro led, 18/4 schedule, 20-25 °C 39% rh, watered once every 2/3 weeks, in the last couple times I strongly reduced the nutrients since I saw what seemed to be a slight burn, but now the situation went a bit far beyond that.

It all revolves around the yellowing of some fan leaves in 2 of my three plants, coupled with burned tips, very red stems and brown "patches" within the yellow leaves.

My best guesses are that:

1) It Is a light stress issues since i switched my led old 100 w led with the 150 w version and since they flowered they've also gained a lot of height, reaching ~30 cm from the lamp. Also the lower plant isn't affected very much, except for some slightly yellow tips If this is the case It should be fine, i lowered the intensity to 75% and It could be good, but i could be wrong for sure...

2) It's a nutrient problem, in this case i can't really tell, but i suspect either a potassium deficiency (most likely viewing the photos imho) or toxicity. The last couple of times i watered (twice in a week) i reduced the dose almost at 0 since i saw some burnt tips and thought It was potassium toxicity.

Here some photos, thanks for the help as usual!

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The Aspie Toker (Thu Mar 18, 2021 4:33 am)

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Re: Help for a "mistery"

Post by WhIpLaSh »

What size pots are they in?

You only water them every 2/3 weeks or days?
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The Aspie Toker (Thu Mar 18, 2021 4:34 am) • frankthirtyspears (Thu Mar 18, 2021 11:02 am)

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Re: Help for a "mistery"

Post by GMO »

maybe just a bit of dry back and salt burn. have them come close to wilting?
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camkush (Wed Mar 17, 2021 11:35 pm) • The Aspie Toker (Thu Mar 18, 2021 4:34 am) • frankthirtyspears (Thu Mar 18, 2021 11:02 am)
“If you can't explain it to a six year old, you don't understand it yourself.” -Albert Einstein

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frankthirtyspears
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Re: Help for a

Post by frankthirtyspears »

WhIpLaSh wrote:
Wed Mar 17, 2021 11:19 pm
What size pots are they in?

You only water them every 2/3 weeks or days?
They are in 6,5 lt pots, i water them every 2/3 days (when i feel the pots are lighter basically)
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WhIpLaSh (Thu Mar 18, 2021 11:13 am)

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Re: Help for a "mistery"

Post by frankthirtyspears »

GMO wrote:
Wed Mar 17, 2021 11:28 pm
maybe just a bit of dry back and salt burn. have them come close to wilting?
It could be, even if i haven't noticed wilting before, just a few burns, spots and a slight yellowing of the fan leaves.

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Re: Help for a "mystery"

Post by Bulls »

I think it's Number 1. The LED is a bit close..you should have that distance but in inches.
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frankthirtyspears (Thu Mar 18, 2021 6:59 pm)

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Re: Help for a "mystery"

Post by frankthirtyspears »

Bulls wrote:
Thu Mar 18, 2021 12:13 pm
I think it's Number 1. The LED is a bit close..you should have that distance but in inches.
Lowered the intensity at 75% than before, gonna update!

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Re: Help for a "mystery"

Post by frankthirtyspears »

Small update: i think i figured out the situation, since the light was very strong, It made the plants suck up all the phosphorus and caused a deficency (i think It should be that 99% since the fan leaves started to purple and some lower leaves started to wither exactly like a phosphorus deficency).

Now i'm definitely going for a heavy dose or Bloom nutrient and a pH check-up, just to be safe (even though using organic stuff It should regolate itself for the most part).
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2-Scoops (Sat Mar 20, 2021 2:14 pm)

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