Brown spot on Tangerine Dream, PICS

This Tangerine Dream is growing in organic soil. I removed several leaves 4 days ago to deter any spread if need be and it has reappeared. I had problems with mites 3 months ago but have seen no evident of return and don't think this is a return. This appears to the only plant affected, and is the only TD also.
I would like to make sure its not something that's going to spread before I get into flower.
I am and organic grower and void chemicals.
Thanks

Is that grit on the back of the leaf or just dirt can't see in pics properly

Frit. Not grit

Try this chart. I think you may have an Mn deficiency

http://www.420magazine.com/forums/problems-pests-disease-control/66208-cannabis-nutrient-deficiency-table-great.html

fragle said:

Is that grit on the back of the leaf or just dirt can't see in pics properly

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I believe its just dust on the plant.

fragle said:

Frit. Not grit

Click to expand...

What the hell is "Frit"?

frit is a sap sucker, they are very small and almost a perfect rectangle there is 100s of different kinds but they are usually dark in colour.

looks like thrips....
look at the little black dots on the backside of the leaf
But if its nutritional,then it could be Mg or P def

Any other input here?

how much do you need? do you have a infestation of pests? if not then check your ph, do the leafs start to yellow and have almost cloud like nicrosis? or does it come straight in with spotting?

light green cloud like then to spots is mg spotting with yellowing is usually p.......check your ph

with the red stems i would say its p