I doubt it was over watered, I was away for 2 days and the soil dried out, and the leaves looked the same as they did when I was watering a little more frequently. The soil drains well and doesn't stay wet too long.
So, I used Happy Frog soil with bottom 1/3 of pot containing amended super soil sold on Amazon mixed with more Happy Frog. It's supposed to be PH balanced for Cannabis without having to add anything. I haven't added nutes since this method is supposed to be "set it and forget it"
But I'm wondering now if I should get a PH tester and see what's going on.
It's probably good to have a decent soil probe anyway but let's hope she grows out of it. Hopefully just the roots hitting the bottom layer

Is your light 300w at the wall? What's the model?


Hats off to you , your first grow is blowing mine away. I bet you will have a harvest above what you are hoping so keep it up your doing something right. 
