Hi all, I have a head scratcher. I have 6 x skunk #1 in my room, all fed via drip irrigation 3 times per day until 30% run off, all in 8L fabric pots. I have 2 x 600w air cooled HPS lights and one 1200MarsHydro LED (600w equivalent). Nutrients are simple Canna A and B, Sumo boost, and Buddhas tree PK 9-18 as I am 3 weeks from harvest. I have good extraction, fresh air coming in from outside (loft grow), and fan ossilating around.
5 out of 6 plants look awesome, no problems, stems are like chair legs but one plant, in the middle, started with a orange/brown rusting on the bottom fan leaves just after I turned to flower. I did plenty of flushing, as first I thought maybe this plant might have locked out but as time has gone on I would say 80% of this plant is now infected with this dying, rusty leaves. However my buds are just as good as the other plants, and it might well be okay. Also the stem on this plant is also a bit rusty tainted.
I just cant seem to diagnose it from looking at charts, its a bad case of whatever it is. I am ruling out rust rot, as I have rubbed the leaves and it hasnt come onto my hands, and my temperatures and nice and comfy, ranging from 23degrees daytime to 18 nightime, and my humidity is under 50%. The closest I have seen on a chart is calcium deficiency, but calcium is an immobile nutrient and deficiencies would start with the top leaves.
Magnesium is a possibility I cant rule out, I have a bottle of plant magic magne cal on the way as another troubleshoot. I have some pictures attached, however the light isnt the best, girlfriends don't make good photo takers, but you can make out whats going down. Any feed back helps as always.