Skunk #1 clones in DWC - 5.8 PH, Water temps ~70-73F, 400W MH, PPM of Flora Nova Grow is around 500-550 PPM in RO water. Some of the leaves are getting to look like this. Beginning with tiny spots and then growing rusty like this. I did have some problematic pH problems because I thought I was getting it to a normal pH but my meter was off so it was like 5.3-5.5 for a week. Fixed now. BTW, the plants are at 8 days veg from clone