Yellowing of Leaves. Please Help.

In the last day or so i have noticed that some of the leaves on my plants are starting to develop this Yellow spots on the leaves, and i am not sure what it is from. These plants are about a month old and are kept under 24 hour HPS light with a fan on them at almost all times. I have attached 2 photos of the yellowing i am talking about. I am new to this, and I greatly appreciate any advice and tips you guys can give me.

Thanks.

What kind of dirt and nutrients you're using?
Looks like some type of deficiency!

I would say its a nitrogen deficiency. A month is about the time that your plants absorb all the fertilizer from your soil. Its time to start adding some nutes to your watering.

I am using Miracle Gro Potting Mix, and i have been adding a small amount of Miracle Gro Water Soluble Orchid Food, which has a N-P-K ratio of 30-10-10. I have been adding the nutes in a small amount because i had read that too strong a solution will damage the plants.

DocGrower said:

I am using Miracle Gro Potting Mix, and i have been adding a small amount of Miracle Gro Water Soluble Orchid Food, which has a N-P-K ratio of 30-10-10.

I have been adding the nutes in a small amount

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because i had read that too strong a solution will damage the plants.

Click to expand...

Start adding the nutes full str, as it says on the packaging.

check this out http://www.marijuanapassion.com/forum/showthread.php?t=54233

Thanks for all the help guys. I have read some other forums and gathered some other information which is starting to lead me to believe that it might be a salt build-up that is leading to a nute deficiency. Do you guys think i should do a quick flush of the pots that have these infected leaves?