What caused these brown spots? (pic)

My baby is about a week old and has developed these brown spots on only one of it's leaves. No other leaves on the plant have them, and none of the other plants have them either (they're all the same age, strain, nutes, etc.). Does anyone have any suggestions what may have caused these particular types of spots?

I have examined for pests but could not find any.

Here are the specs of my setup:
-Hindu Kush (100% indica)
-600w MH with a cool tube
-Humidity of 50-60
-Temp 78-83F
-75% coco 25% perlite medium with a tablespoon of mykos

I hand water ½ a cup every 3 days. This is the mixture of what they're fed:

Per gallon:
-Dynagro protekt 16ppm
-Dynagro foliage 35ppm
-rapidstart ¼ teaspoon
-GH calmag 1/8 tea
-Age Old Kelp 1/8 tea
-Earth Juice Molasses ¼ tea

Any and all input is greatly appreciated!


Cheers

Birth mark. Them leaves will eventually die anyway since they are so young. no worries keep it movin frodo.

cassinfo said:

Birth mark. Them leaves will eventually die anyway since they are so young. no worries keep it movin frodo.

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thats the best way to put I've ever heard. A birthmark ! haha thats what it is good luck

Yeah it hasn't spread or gotten worse, so I am not really too worried about it anymore. I guess it is just a 'birth mark' lol. Thanks for your replies lads, much appreciated.