Rust Spots week 4 flowering Only top leaves

Hi All,

I am having a problem with 1 out of five plants currently in the fourth week of flowering. I am growing white wiidow, in soil, using fox farm ocean forrest soil and fox farm nutes. I am growing under a 400W HPS. I have attached a picture of what the problem looks like. The pic is a little blurry but there appears to be rust colored/browinsh spots developing on some of the leaves at toward the top of the plant. The spots are not on the lower leaves. Could this be due to heat stress? Any other things that I can do to fix?

your pic is crap----looks like litter to me----you want a correct diagnosis? then give us a clear pic of the leaf or infected or subject area as well as an over all shot to see the over all health. FYI

easy cali lol a bit blurry yes, but were still able to see distinct spots with a brown color...looks like maganese deficiency, possibly just not enuff or from nute lockout due to ph levels...add some CalMag and see what happens. light burn looks diff, the leaves curl and brown at the tips, a much more distinct look....good luck!