I had the same problem I was in DWC so I am not sure if it will help out. I kept my ph at around 6.0 and it started spreading. I went and purchased some cal-mag and mixed 1tsp in a gallon of phd water and used it in a spray bottle and sprayed them about 4 to 5 times a day and then added 1tsp per gallon of water to my res two days later they are fine.
ELEL95 Reviewed by ELEL95 on . Calcium Deficency??? Hello all, i'm back with another question for ya. Im in week 5 of flower and have started to notice the brown spots and yellowing on the lower fan leaves. At the time i chalked it up to the plant doin some maintance by killin off the large suckers that weren't producing enough sugars etc. Well i trimmed off most of those trouble leaves and the spots/yellowing are showing up on the newer growth up top. Now i have done some extensive research on this issue and everything i find points towards a Rating: 5