Is this Cal/Mag deficiency?

[Metacanna]

Hey,

My plants are flowering for 3 weeks and in the last week I noticed some leafs turning pale green, then yellowing in the bottom and middle of the plant, doesn't look like nitrogen problem.
I guess it's a cal/mag issue so I watered with Epson salts yesterday, so far no recovery. I need to know what it is so I can fix it asap before all leafs start falling, as half of each plant is already affected.
Take a look into the pictures please and let me know what do you think.
Thanks in advance

 

[ANC]

Used coco without calmag buffering? It will keep sucking it out of your nutes before the plants can get it.
That mess didn't happen in a day, and isn;t going to go away in a day either.

 

[Metacanna]

I'm growing in soil.
I'm not expecting to get rid of the problem in one day but the deficiency is progressing very fast, I need to take action to stop the progression but I'm not sure what it is.

 

[JimmyTheNewb]

I could be wrong but if cal mag doesnt fix it id try phosphorus

 

[Buba Blend]

I'm growing in soil.
I'm not expecting to get rid of the problem in one day but the deficiency is progressing very fast, I need to take action to stop the progression but I'm not sure what it is.

Pictures of the whole plant might help.
Looks like it need N.
watering habits are always suspect for lots of problems so it doesn't hurt to check yours.
what size pot?
What type of soil?
How often do you water?
How much water do you use for each plant?
How do you check your soil to know it is dry and time to water?

 

[Metacanna]

Pots are 3 gallons size. I have been watering half a gallon each plant every 5 days, I know when I need to water by checking the pot weight and humidity on the soil surface. I'm growing with LEDs, so less evaporation due less heat.
Soil has a nice amount of coco and perlite (30%-40% or so) for good drainage.
However, I don't discard the possibility of overwater. I'm reducing the amount of water to see how the plant respond.

You are right, I should have taken a picture to the whole plant. I will do it tomorrow.

Last grow same thing happened, then I provided some epson salts and the problem didn't evolve anymore. However I still not quite sure the problem is really related to cal/mag deficiency or if it is something else.

 

[Dynamo626]

Pictures of the whole plant might help.
Looks like it need N.
watering habits are always suspect for lots of problems so it doesn't hurt to check yours.
what size pot?
What type of soil?
How often do you water?
How much water do you use for each plant?
How do you check your soil to know it is dry and time to water?

my thoughts exactly. looks like n. whats the actual draw from the wall of the led. not what the manufacture claims. what brand soil or did you mix it yourself?
the yellowing will not go away you have to watch newer growth to see if your problem is fixed or still progressing

 

[Metacanna]

I built a 250W Cob LED painel, but it's dimmed to operate at 170W. My grow space is 0.42m2, light is providing 800 PPFD, more than that can stress the plants so I prefer to play safe.

The soil is a mix of decent potting soil, German brand, don't remember the name, plus 30%-40% perlite and coco plus 20% vermicompost.

If the deficiency is nitrogen, it might be something that is blocking the uptake, it's very unlikely that nitrogen is missing when feeding.

I went on holidays last week and watered a bit more than normal as I was concerned that the plants could dry out while I was away. Not sure if I overwatered , if so, my ladies are overeacting! Drama queens!

Some pictures of them 2 weeks ago.

 

[Buba Blend]

Pots are 3 gallons size. I have been watering half a gallon each plant every 5 days, I know when I need to water by checking the pot weight and humidity on the soil surface. I'm growing with LEDs, so less evaporation due less heat.
Soil has a nice amount of coco and perlite (30%-40% or so) for good drainage.
However, I don't discard the possibility of overwater. I'm reducing the amount of water to see how the plant respond.

You are right, I should have taken a picture to the whole plant. I will do it tomorrow.

Last grow same thing happened, then I provided some epson salts and the problem didn't evolve anymore. However I still not quite sure the problem is really related to cal/mag deficiency or if it is something else.

I'm gonna paste what I just said to another guy. Might apply more to him than you since you wait 5 days.

If they are plastic pots with drainage holes the next time you plan to water check the soil an inch or so through the drainage hole and see if it is dry, moist or wet right before watering. You should also get a cheap $10 moisture meter.

I could be wrong in the way I phrase this so correct me if I'm wrong or if it is not useful info cause I haven't said this to someone before.
Not giving your plants the dry period needed before watering can affect N in soil. There are Nitrogen fixers (bacteria) in the soil that operate best when the soil is given the right amount of a dry period before watering.