Hello guys, I've got 5 Dinafem Moby Dicks here, a month into veg, pH is 6.3 - 6.8 in pre mixed soil, using the same setup as my previous grows except that I have added Cal-Mg. Humidity is always less than 40%. Temp is 73-77 with a small fan blowing a gentle breeze. LED, 12 inches away from the canopy. But I got this white corrosion type problem on my newly formed leaves. I don't have a ppm meter, but the only thing that I have changed is the addition of Cal-Mg for the past 3 feeds. I had to do it again today and I stopped using it just in case. Please tell me if you identify the problem. I don't want that to give me a failure!