Yellow leaves, and spots on the leaves. What is causing this.

I have two plants with two different problems. One of the has 3 yellow lower leaves, and the other has brown spots on
most leaves.

I suspect it must be a pH problem as i've grown from clone with the same equipment and nutes before, but different soil
and different house. It doesn't matter i'll be getting some test strips soon.

I just want to know what type of deficiency or toxicity is causing this.

Both: Male and Female


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bump............

It looks to me like the same problem I've been having, i believe mine is magnesium deficiency but no one has confirmed, the reason i believe i have magnesium deficiency is because of this video, i seem to have all of the symptoms he describes, leaves canoeing, purple stems, leaf tips burnt and curling upward, and leaves yellowing from the tips to the stem then developing brown spots, what about you? Here is a link to my thread, tell me what you think? https://www.rollitup.org/marijuana-plant-problems/560464-plant-problem-progressing-rapidly.html
[video=youtube;FI9FIy7rvww]http://www.youtube.com/watch?v=FI9FIy7rvww[/video]

lockout ph issues and a cla-mag deff