Magnesium deficiency mephisto

[Mat1979]

Hi, I hope someone can help me. I'm growing mephisto under 50w cob lights. In Coco/perlite mix and feeding all canna nutrients.
I think my problem is a magnesium deficiency which I keep getting just as they move into flower. I use calmag each feed at 1ml per liter minimum up to 1.5ml. If anyone can be of assistance it would be much appreciated. Here's some pics.

 

[Hanzo-hattori]

Yep looks like mag def to me classic signs and starting from the bottom of the plant. Cal mag issues normally arise during early flower. Check your ph if she is good just give her a little extra mag to get her right

 

[AutoWonders]

It isn't terribly unusual for the need to double calmag amount.

 

[Mat1979]

Ok thanks chaps, is there a max per litre with calmag?

 

[namvet25]

5ml per gal is the usual dosage during flowering.

 

[Mat1979]

Yeah that's a lot more than I have been giving

 

[Hanzo-hattori]

Yeah that's a lot more than I have been giving

It’s not bro there are roughly 4L in a gallon

 

[Mat1979]

Ah yeah sorry, I was mashed