Layer of leaves looks to be eaten off?

[Narkgrowop]

Hey guys, I am growing some Northern Lights Auto and this is my first grow. They are about 20 days old. Growing under a 600w LED in fox farm soil at 20/4 light cycle. I noticed yesterday that there were some spots on the leaves that look like something ate the top layer of the leaf off. I haven't spilled any nutes or anything else on the leaves, so I'm not sure what it could be. The only thing that has gotten on the leaves is some water drops when I watered last, however there were no nutes in that water. Let me know what you guys think it could be!

 

[some1else]

I'm guessing a light burn from water drops on the leaves. Just like you can burn things with a magnifying glass.

 

[Narkgrowop]

That's what I had thought until I checked today and there are more spots. Anyone else have any idea?

 

[Narkgrowop]

Anyone else? Seems to have gotten worse:

 

[Narkgrowop]

Anyone??? Here are some more photos, I decided to cut two of the fan leaves off:

 

[daTenshi]

Maybe answering some questions might help diagnose the issue.

How to Ask for Grow Support