Help with deficiency

Hey everyone I need some help with figuring out this problem.

This is a indoor grow
-Medium is fox farm happyfrog in 2 gallon pots
-Watering schedule is 1000ml every 3-4 days depending on weight and soil dampness.
-using green house seed company short powder feed every other watering. They have only had one dose. They started curling up before this was introduced
-I just switched to a 12/12 light schedule about 7 days ago

I have 2 cabinets all of the same strain(white widow) and all were started at the same time.

The 5 in veg cab seem to be fine, a few burnt tips but nothing serious.

The 6 I have in my flower cabinet is concerning me. They started to have very narrow leaves curling up and tacoing towards it self. Old growth is very very dark green with the edges of the fan leaves turning brown and black. new growth looks yellowish light green.

Any help is much appreciated
Cheers and happy growing

Heat stress and magnesium deficiency both.

The plants look like they started out with a Nitrogen excess (super dark green leaves) to a Mg shortage. For sure you need Mg...or it's being locked out. Epson salt is your friend.

As Hotrodharley suggested, heat stress may also play a role. Can you elaborate on your temps, humidity, lights being used and distance to the plants, etc?

Are you pH'ing your water and feed? If so, to what?

CannaCountry said:

The plants look like they started out with a Nitrogen excess (super dark green leaves) to a Mg shortage. For sure you need Mg...or it's being locked out. Epson salt is your friend.

As Hotrodharley suggested, heat stress may also play a role. Can you elaborate on your temps, humidity, lights being used and distance to the plants, etc?

Are you pH'ing your water and feed? If so, to what?

Click to expand...

Temps have been pretty consistent around 24 Celsius with lights on 20 with lights off. Humidity around 50-60% Using a diy LED light with 6 Bridgelux eb2 strips. It’s hanging about 12” away slightly dimmed. maybe it’s too close? First time using led so still figuring it out.

No I have not been ph’ been waiting on my kit from amazon. What would be a good reading 6.5?

Rattlehead121 said:

Temps have been pretty consistent around 24 Celsius with lights on 20 with lights off. Humidity around 50-60% Using a diy LED light with 6 Bridgelux eb2 strips. It’s hanging about 12” away slightly dimmed. maybe it’s too close? First time using led so still figuring it out.

No I have not been ph’ been waiting on my kit from amazon. What would be a good reading 6.5?

Click to expand...

That light is WAY too close.

https://ledlightsnation.com/tips-on-growing-marijuana-indoors/

Heed Hotrodharley's advice on that light...

6.5 pH would be a good starting point on a soil grow...some of the soil growers may be more specific in a number or range so perhaps some of them will chime in. I use coco which is a slightly different animal.