I'm growing in a 2x4 room with 1200w LED light fixture and using soil that feed for 6 months, it's only been 2 months.. I've been trying to get the pH right..my water and water soil is over 7 so I added pH down to make it 5.8.. I tested the run off and it was great, tried to test the soil but it seems to me that t my brand new pH soil tester is not moving on the scale..and I'm getting some fan leaves that have crispy brown spots on the leaves. I just watered yesterday and I'm not giving any food in the water.. should I give it a little bit of food??