OK, hoping someone can help. These plants are 35 days old (day 28 of 12/12). I am using the Advanced Nutrients 2+ Bloom (medium feeding) program. I continually give them 2 feedings of nutrient (at 6.3ph) and 1 feeding of regular water (at 6.3ph). I foliar spray with Growth Excel just before the lights come on about 2-3 times a week (tho I dont PH the water I use for this foliar spray - should I?). They are growing in ProMix HP under a couple of 1000 w HPS's. Temps are between 17c/65f and 26c/83f. Air circulation is good. Humidity is not a problem. Starting at about day 20, I started to notice rust spots on some of the leaves. It got progressively worse day by day. I started reading/asking around and came to the conclusion that it was most likely a defiency of calcium and/or magnesium, so around day 27 I gave them Cal-Mag plus (5ml/gallon). I have since given them the Cal-Mag of 3 of the 4 waterings since but the problem seems to be spreading (from the lower leaves up). I tested the runoff of my soil on a couple plants. Using nutrient water at ph 6.3, I get a runoff of 5.0-5.3. I beleive this is too low. Am I right? Does this have something to do with my problem?. Is there something I can/should do? Any ideas would be appreciated.
jpriest66 Reviewed by jpriest66 on . rust spots getting worse (pics) OK, hoping someone can help. These plants are 35 days old (day 28 of 12/12). I am using the Advanced Nutrients 2+ Bloom (medium feeding) program. I continually give them 2 feedings of nutrient (at 6.3ph) and 1 feeding of regular water (at 6.3ph). I foliar spray with Growth Excel just before the lights come on about 2-3 times a week (tho I dont PH the water I use for this foliar spray - should I?). They are growing in ProMix HP under a couple of 1000 w HPS's. Temps are between 17c/65f and Rating: 5