Is this magnesium deficiency? How to Fix?

Based on what i can find on the web, i think im having a magnesium deficiency issue. I’m not sure how to fix it with my setup. Any advice would be great!

That Details:
Banana Kush Auto
4weeks from sprout

Setup:
SF Grow Tent 2.5’ x 2.5’ x 5’
SF 1000 Lights (height 24inches)
3gal Autopot Coco Perlit 70/30

Environment:
Light Cycle: 18/6
DLI: 35
Temp: 78° F
RH: 66%

Nutes:
Silica (Armor-Si )
Jacks Part A
Jacks Part B
Epsom Salt
PHed to 6.0
EC: 2.0 (at mixing 2.0)
EC: 2.2 (Current) ( dilute to 2.1)
Water Temp: 78° F
PH 6.0 (After recalibration




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It does and possibly calcium. What ph meter are you using and have you calibrated it recently?

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BluLab PH Pen. I recalibrated it today. My reservoir PH reading was 6.0 before recalibration and after, the reading was 5.9.

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That’s good. I’m thinking a lockout due to excess in the medium or a plant that’s very hungry for cal and mag to where you could do a water run through to see what the coco ec is, if that’s good, increase dosage of epsom and part A. Last thing would be to make sure the silica is added first and well mixed before adding anything else

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Can I do a water flush (flush from the top) at this point since she’s been bottom fed for a couple weeks now? Could I push any salt build up in the coco i can’t see yet into the root zone?
Yeah i typically start with silica and let it sit for 3-5 mins before adding the rest of the nutes.

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Im not sure with auto pots but I see no reason why you can’t remove them to “flush” if the need arose. I’ve never used them. Maybe @OGIncognito can help in that department. I believe they’ve used them for a while.

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Appreciate the tag Bobby D, @NewGuy2 I’ve flushed a few times using auto pots but only when needed. Your numbers are on point and I would give it another week of bottom feeding. You’re providing the Epsom for magnesium so no issue there. Depending on the plants age and root growth at transplant when turning on the auto pots the nutrient solution can sit in the tray and the PH can drift out of range. More roots and older plants will consume the nutrient solution in the tray faster. You can always check the PH in the tray just for GP. Leaf symptoms resemble a smidge of a PH issue but overall she looks good :love_you_gesture:

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Thanks bud, great explanation!

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My pleasure Grow Bro, on my 5th year running these and have experienced a few issues :love_you_gesture:

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So I’m guessing you like them then. I may need to experiment with them. You running coco too or soil?

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I really like them. I’ll even run 1 gallon cloth bags in the older 2 gallon trays. I just started using coco loco plus additional perlite after I started working out of town Monday-Friday. The PH range is too tight for coco and res PH drifted above that. Works great when I’m home to adjust every other day or so. I’ll set the res PH for coco loco at 6.3 and let it drift through the week and generally peaks at 6.7 by the time I get home. Knock on wood it’s working. Give a single pot at up a try, you’ll be hooked. I have the old style 2 gallon plastic pots and the newer 3 gallon set up for fabric bags. The cloth is much better :love_you_gesture:

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Appreciate the great feedback @OGIncognito.
The tray reads 6.1 and shes 4wks old from sprout. I started he in the final pot to avoid transplant shock. The Autopot got turned on 2 wks ago once her leaves reached the egde of the pot on all 4 sides. I’ll keep an eye over the next week and see if she clears up or not.. Thanks @BobbyDigital

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I’ve been bottom feeding plants for several years now in cloth pots and I can’t recall the exact motivation to do so but I believe it’s because of reading about this system. After the first grow I never went back to top feeding. It just made more sense to give the water seeking roots the water.

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Winner winner for me as well :love_you_gesture:

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I have a contrary opinion and am not a fan of bottom feeding. It presents challenges that won’t be properly managed among newer growers. It can be a significant pH problem if using salty nutes like FF’s Trio.

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I’m listening – please continue.

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Me too. Feed the info bro. Sponges here soaking it up.

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@NewGuy2 welcome back.

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Thanks, its been awhile.

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When you do this is there any concern for the majorly of coco in the pot to be hydrophobic and bleeding nutrients as coco typically would if allowed to dry out? I haven’t used autopots, but I’m assuming top half or more stays pretty dry once bottom feeding is established.

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