A little help concerning yellow/spotty leaves

Hi,

This is my first post and glad to be part of the team, I've got 8 lovely ladies:

2 - OG Mandarin
1 - Blueberry
1 - Super Lemon Haze
1 - OG Kush
1 - G13
1 - 1 Mango Kush
1 - Unknown, given to me by neighbour in rough shape (doing better now... lol)

Some of the leaves on the Blueberry, OG Kush and Mango are turning yellow with brown spots, the leaves on the G13 are always droopy...

This is what I'm doing right now:

Water twice per week, once without any nutes and once with nutes, everything is PH'd at 5.8-6.0, half suggested general hydroponics go box, I'm growing in Pro MIX HP, in bags, my EC is always between 1.0 and 1.2. The plants were sprouted late December. I use room temperature tap water, city water. RH is stable at 65%, temperature at 22 degrees celsius/day and 19 degrees celsius/night. 4x8 grow tent, 6 inch fan with 2 1500 w lights and 1 QB 1000w light. 2 room fans constantly hitting leaves.

When I check my runoff PH it gives me 6.7....

This is my fourth grow and first grow using Pro Mix HP, the roots seem to love it but i'm not sure since I seem to get issues with it, being that this is my first grow with it, i'm wondering what I am doing wrong.

I've also learnt that next time i'm sticking to one strain, this is a lot easier and I feel like there is a huge difference on how strains react to different environments and nutes.

Any help would be appreciated.

Thank You

PLEASE put images as thumbnails, it's taking me forever to load even one image since they are all loading.

Check the pH of the medium with a quality soil pH meter like bluelab, I suspect it's off regardless of the input pH. In this case likely high. Runoff isn't reliable way to check medium pH.

Gabbers7718 said:

everything is PH'd at 5.8-6.0

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You ideally would want 6.5 BUT I think the medium is somewhere in the 8's. In that case we would feed much lower to beat the soil into submission.

Renfro said:

You ideally would want 6.5 BUT I think the medium is somewhere in the 8's. In that case we would feed much lower to beat the soil into submission.

Amazon.com : Bluelab PENSOILPH pH Pen for Soil, Coco, Rockwool and Solution, Easy Calibration : Soil Testers : Garden & Outdoor

Amazon.com : Bluelab PENSOILPH pH Pen for Soil, Coco, Rockwool and Solution, Easy Calibration : Soil Testers : Garden & Outdoor

www.amazon.com

Click to expand...

Should I flush 3x the volume of the pots?

Thank you for the response

Gabbers7718 said:

Should I flush 3x the volume of the pots?

Thank you for the response

Click to expand...

NO



Why are you water/feed cycling? If you want to continue to water/feed like that, I would bring the EC up around 2-2.5. At your EC you should be feeding every time.

Promix= hydro so pH should be 5.6-6.4 with the sweet spot 5.9-6.1, think you're good there.

Temps under LED need to come up 25c night 28c day, you don't have any IR to heat the leaf surface, so the ambient temps need to be warmer.

Make these 2 changes and you will see an improvement guaranteed


PS if you have the full GH line, use their feed chart for drain to waste. It's perfect.

Read over this thread, it's a similar situation but reversed (pH of the medium is low). Pay close attention to the correction described by @DoubleAtotheRON and you will get the general idea.


Flushing will just make things worse, the plants want food.

A corrective feed with a pH that is, in your case, lower than normal is the way to go IME. Each feed the pH will swing through the goldilocks zone allowing the plant access to everything plus you will beat the medium into submission.

Renfro said:

Read over this thread, it's a similar situation but reversed (pH of the medium is low). Pay close attention to the correction described by @DoubleAtotheRON and you will get the general idea.

what's this

hey guys, hope all is well i am really new to this and trying to figure out stuff as we speak. but what my be causing this to my plants

www.rollitup.org

Flushing will just make things worse, the plants want food.

A corrective feed with a pH that is, in your case, lower than normal is the way to go IME. Each feed the pH will swing through the goldilocks zone allowing the plant access to everything plus you will beat the medium into submission.

Click to expand...

Thank you, that thread is great!

its.always.420 said:

NO



Why are you water/feed cycling? If you want to continue to water/feed like that, I would bring the EC up around 2-2.5. At your EC you should be feeding every time.

Promix= hydro so pH should be 5.6-6.4 with the sweet spot 5.9-6.1, think you're good there.

Temps under LED need to come up 25c night 28c day, you don't have any IR to heat the leaf surface, so the ambient temps need to be warmer.

Make these 2 changes and you will see an improvement guaranteed


PS if you have the full GH line, use their feed chart for drain to waste. It's perfect.

Click to expand...

Thank you, i'll increase the EC!