This is my first grow, after many heat issues, I've finally gotten my plants started. Now my biggest happiest plant had little brown/black spots all over the fan leaves. They got larger overnight so I clipped off all of the infected leaves. Any suggestions on what might be causing this? This plant has had some yellowing tips but that has improved over the last week or so. Here are my details: 6 plants: 2 ice, 2 red dragon, and 2 durban poison soil is 50/50 peat moss/Miracle Grow potting soil (I know, not the best, but it was all I had) Lights: 6 T-4 Fluorescent lights on 18/6 Nutrients: General Hydroponics Flora Nova Grow every 3rd watering Adjusting Tap Water pH w/pH down to ~6.5 temp is between 70-80 unless the power went out like today Humidity is ~50% Have CO2 via Yeast/Sugar water Please let me know if you have any ideas about probable cause or if you need further information. I have also attached the pics from the yellowing leaves on the Durban Poison and Red Dragon which I believe was a N overload. Thoughts?
I`m new to all this stuff and am still on my first grow but I did find this grom a Google search that I copied from this website: Nutrients PH Problems On Marijuana Plants Spots Symptoms That Appear Diagnosing Marijuana Cannabis Plant Abuse Problems Charts and Photos Iron Toxicity Excess accumulation is rare but could cause bronzing or tiny brown spots on leaf surface. Manganese is involved in the oxidation reduction process in the photosynthetic electron transport system. Biochemical research shows that this element plays a structural role in the chloroplast membrane system, and also activates numerous enzymes.
see how the leafs have a yellow frame around them... classic mag def... get some cal mag and give em a lil shot...
How should I add it to the plants? Just sprinkle Epsom salts on the soil before watering? I've noticed a third plant with the same symptoms. Also, should I trim off the leaves with the spots?